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Don J
2012-May-08, 06:56 PM
I want to know if there is actually observation of the creation of new galaxies or if everything is already set -up in that matter ?

antoniseb
2012-May-08, 07:21 PM
I want to know if there is actually observation of the creation of new galaxies or if everything is already set -up in that matter ?

I suppose it depends on what you mean by "new galaxies".
- There are dwarf galaxies forming as debris from the collision of larger galaxies.
- There are low surface brightness galaxies which may have been around for a very long time, but have been very slow about getting local densities high enough for star formation.
- There are new galaxies being created from the collision of old ones.
- There are very distant (z>6) galaxies which are clearly seen as new.

I suspect that you are asking about local galaxies forming from pristine primordial gas clouds that have thus far escaped condensing into galaxies... I don't know of any examples, or remember any papers discussing examples of this.

Don J
2012-May-08, 07:46 PM
I suppose it depends on what you mean by "new galaxies".
- There are dwarf galaxies forming as debris from the collision of larger galaxies.
- There are low surface brightness galaxies which may have been around for a very long time, but have been very slow about getting local densities high enough for star formation.
- There are new galaxies being created from the collision of old ones.
- There are very distant (z>6) galaxies which are clearly seen as new.

I suspect that you are asking about local galaxies forming from pristine primordial gas clouds that have thus far escaped condensing into galaxies... I don't know of any examples, or remember any papers discussing examples of this.

Thanks ! So it is safe to consider that the Universe is actually in a steady state codition even if it is expandind ?

antoniseb
2012-May-08, 07:51 PM
... So it is safe to consider that the Universe is actually in a steady state codition even if it is expandind ?

I don't know what you mean by "steady state condition". If galaxies are continuing to age, and star-forming is continuing to drop off after a peak five to eight billion years ago... what is steady?

chornedsnorkack
2012-May-08, 07:54 PM
What is Minkowski Object becoming?

Don J
2012-May-08, 08:06 PM
I don't know what you mean by "steady state condition". If galaxies are continuing to age, and star-forming is continuing to drop off after a peak five to eight billion years ago... what is steady?

Steady state in the sense that there is only an evolution of already existing objects.

antoniseb
2012-May-08, 08:12 PM
Steady state in the sense that there is only an evolution of already existing objects.
You must be aware that the term "Steady State Universe" has some pretty well established meanings that are far outside of your usage here... right? The Hubble Ultra Deep Field, and other deep surveys have pretty much completely invalidated the Steady-State idea, but there are still people who don't like the Big Bang, and are looking for ways to re-assert SSU as an alternative. You, as a supporter of non-mainstream ideas should be careful about using or misusing such terms.

Shaula
2012-May-08, 08:20 PM
We see galactic mergers in progress, and the aftermath of them. So no, it is not steady state at all. Just that things don't happen quickly out there.

Don J
2012-May-08, 09:00 PM
We see galactic mergers in progress, and the aftermath of them. So no, it is not steady state at all. Just that things don't happen quickly out there.

I am not saying that nothing is happening with the actual existing stuff.

Just that everything seem to be already set-up in term of creation of new galaxies forming from pristine primordial gas clouds.

Let me rephrase my previous assertion (post 3)

Is it safe or (conceivable) to assume that there is a finite number of Galaxies in an infinite Universe ?

antoniseb
2012-May-08, 09:09 PM
... Is it safe or (conceivable) to assume that there is a finite number of galaxies in an infinte Universe ?
It's doubtful that the universe is infinite. It's likely that the mass of all the matter in the universe is roughly constant. The location of the mass seems to be changing as the voids slowly get less concentrated.

Swift
2012-May-08, 09:19 PM
Is it safe or (conceivable) to assume that there is a finite number of Galaxies in an infinite Universe ?
I would say it is not even safe to say there is a fixed number of galaxies, as galaxies may merge.

Don J
2012-May-09, 01:43 AM
I would say it is not even safe to say there is a fixed number of galaxies, as galaxies may merge.

Does that mean that the ultimate "destiny"of galaxies inside a cluster will be to merge together and ends up with only one big galaxy ?

Ufonaut99
2012-May-09, 02:18 AM
Does that mean that the ultimate "destiny"of galaxies inside a cluster will be to merge together and ends up with only one big galaxy ?
Nothing would be that certain. Galaxies in a typical cluster would moving at a fair speed (which is what led Fritz Zwicky to first postulate Dark Matter), and as per Chaos theory, it would be impossible to forecast precisely the future interactions. eg. I imagine a galaxy could get expelled just like stars get expelled from star clusters.

ngc3314
2012-May-09, 02:23 AM
Does that mean that the ultimate "destiny"of galaxies inside a cluster will be to merge together and ends up with only one big galaxy ?

Unless cosmic expansion accelerates even more dramatically then the cosmological constant interpretation suggests, yes. N-ody systems aren't actually stable, just very long-lived. The long-term state of an isolated cluster of galaxies would be one large central galaxy surrounded by a very extended halo of individual stars and clusters, stripped from the original galaxies during close encounters. In today's clusters, as much as 10-25% of the starlight already comes from these loose stars - it's tricky to pick out their unresolved light from galaxy stellar halos, requiring very careful baffling of the telescope against stray light (although Hubble can see red giants in Virgo, and big ground-based telescopes can find planetary nebulae between its galaxies) . Chris Mihos has done some especially nice work on the Virgo Cluster (http://astroweb.case.edu/hos/Virgo/) in picking out the intracluster light and finding trails indicating individual encounters in the "recent" past.

Fred Adams has speculated carefully about the really long-term future of the Universe, including a book (http://en.wikipedia.org/wiki/The_Five_Ages_of_the_Universe). If you wait long enough, a galaxy would be a central black hole surrounded by degenerate stelar remnants and stellar-mass back holes. If protons decay, there's another whole epoch to consider.

Shaula
2012-May-09, 04:41 AM
Just that everything seem to be already set-up in term of creation of new galaxies forming from pristine primordial gas clouds.
Because they have had time to collapse - this is rather like being amazed that there are no babies being born in a retirement home.

Don J
2012-May-09, 05:08 AM
Because they have had time to collapse - this is rather like being amazed that there are no babies being born in a retirement home.

At the difference than we can still observe the Universe back in time when it was in the "baby state" .

Astronomers find clouds of primordial gas from the early universe

http://news.ucsc.edu/2011/11/pristine-gas.html



The spectrographic analysis of the pristine gas clouds places them in time at about 2 billion years after the Big Bang, or nearly 12 billion years ago. At that time, theoretical models predict that galaxies were growing by pulling in vast streams of cold gas, but these "cold flows" have never been seen. According to Fumagalli, the pristine gas clouds are potential candidates for these elusive cold flows. Further studies are needed, however, to see if the newly discovered gas clouds are associated with galaxies.

It seem from the sentence I have bolded that the theoretical models for the formation of Galaxies is(are) still very hypothetical ?

chornedsnorkack
2012-May-09, 05:26 AM
Because they have had time to collapse - this is rather like being amazed that there are no babies being born in a retirement home.

But not all of them have. Many have missed collapse so far. There are plenty of high velocity clouds around Milky Way, such as Smith´s Cloud, which is right now beginning a collision with Milky Way disc.

When a high velocity cloud hits galaxy disc, it creates a feature like Gould Belt. But what happens when two high velocity clouds hit each other away from any existing galaxy?

Shaula
2012-May-09, 06:59 AM
At the difference than we can still observe the Universe back in time when it was in the "baby state" .
Look again how they found the gas - by looking at absorption features in quasar spectra. We cannot see these clouds in anything like enough detail to spot things like cold flows. We'd only be able to see them if they were happening very close to us - close enough for a direct detection of an extended source and its mapping.

To extend the analogy - it does not matter if there is a maternity unit half a mile away and you sometimes hear babies crying, they are too far away to see in the level of detail required to find out if they wear cloth or plastic nappies.

The current model has a few weaknesses but it makes testable predictions and so far it best matches observations. Otherwise it would not be the current model.

antoniseb
2012-May-09, 11:33 AM
At the difference than we can still observe the Universe back in time when it was in the "baby state" . ...
You are asking here about an area that is pretty new in terms of our ability to explore observationally. Since Hubble and LeMaitre first described the expanding universe, we've been slowly increasing our ability to observe closer to the beginning. You've probably read about some of the observing boundaries, such as the epoch of reionization (which we now think was about z=8, give or take 2). This is something that makes it hard to see things optically or in the infrared before that period, and the initial galaxies had to have formed before that, because it is the light of their first stars that did the reionizing. The JWST should let us observe back to that boundary.

Very recently work has started anticipating the building of the SKA, which should enable us (among other things) to observe highly redshifted Hyperfine Hydrogen radiation (21cm) from time before that, and map how early the concentrations of gas and cold flows happened. So, yes, they haven't been observed directly yet. They have appeared in simulations, so they are expected. The age of the universe when they do get observed will supply some additional tuning parameters to our models of the universe, and let us predict and model other things in more reliable detail.

Cougar
2012-May-09, 12:21 PM
It seem from the sentence I have bolded that the theoretical models for the formation of Galaxies is(are) still very hypothetical ?

Origin and evolution of the structure in the universe (galaxies, large-scale structures) is a central problem in cosmology. Here (www.astro.caltech.edu/~george/ay21/Ay21_Lec08_strucform.pdf) is a good lecture on the subject (9 MB pdf).

TooMany
2012-May-10, 11:02 PM
The Hubble Ultra Deep Field, and other deep surveys have pretty much completely invalidated the Steady-State idea.

How did the Hubble UDF completely invalidate the Steady-State idea?

antoniseb
2012-May-11, 11:46 AM
How did the Hubble UDF completely invalidate the Steady-State idea?
In short, it observed numerous small star-forming galaxies at an early epoch. These were so different from the universe today that the state of the universe is observationally confirmed as not steady. The fact that lots of small star forming galaxies at z~6 is consistent with LCDM is nice for us who are working on the assumption that LCDM is close to right, but the point is that the steady state universe was eliminated as a possibility by HUDF and other such studies of the early universe.

TooMany
2012-May-11, 06:10 PM
In short, it observed numerous small star-forming galaxies at an early epoch. These were so different from the universe today that the state of the universe is observationally confirmed as not steady. The fact that lots of small star forming galaxies at z~6 is consistent with LCDM is nice for us who are working on the assumption that LCDM is close to right, but the point is that the steady state universe was eliminated as a possibility by HUDF and other such studies of the early universe.

Those numerous small, massively star-forming galaxies are only small and fantastically star-forming when you apply the theoretical assumptions of an expanding universe to interpret their distance, size and luminosity. That is a completely circular argument for LCDM.

antoniseb
2012-May-11, 06:13 PM
Those numerous small, massively star-forming galaxies are only small and fantastically star-forming when you apply the theoretical assumptions of an expanding universe to interpret their distance, size and luminosity. That is a completely circular argument for LCDM.


Really? Show me how they could exist as the norm in a steady state explanation of the universe. Show some numbers.

Cougar
2012-May-11, 07:40 PM
Those numerous small, massively star-forming galaxies are only small and fantastically star-forming when you apply the theoretical assumptions of an expanding universe to interpret their distance, size and luminosity. That is a completely circular argument for LCDM.

What about the morphology of those galaxies? That doesn't depend on anybody's theoretical assumptions.


The HUDF shows that ... the early universe was filled with dwarf galaxies, but no fully formed galaxies like our Milky Way. -- source (http://www.spacetelescope.org/images/opo0428b/)



If the universe was in a "steady state," as you inexplicably seem to desire, some of those most distant galaxies would be fully formed. Well, sorry, but they're not. There are no fully formed galaxies like the Milky Way back then.

By the way, the faintest objects in the HUDF are less than one four-billionth the brightness of stars that can be seen with the naked eye. This would tend to indicate that they are, you know, kinda far away. Or is the fact that things generally appear less luminous when they're farther away too much of a "theoretical assumption" for you?

Don J
2012-May-12, 04:40 AM
Is there any datas comparing the surface brightness of galaxies at high and low redshift made from the HUDF survey ?If so what are the results about that comparaison?

Eta
A quick search on the internet returned this ...

http://proceedings.aip.org/resource/2/apcpcs/822/1/60_1?isAuthorized=no

Eta2
I just find the freely available paper on arxiv.
http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2

Is it possible to have the full datas about the surface brightness of galaxies at high and low redshift from the HUDF survey to verify ?

chornedsnorkack
2012-May-12, 10:49 AM
The distance ladder is vulnerable to errors on every step, and to accumulation of errors over several steps - like the notorious mixing of several cepheid types.

How far out is the Hubble constant reliably checked by independent distance measurements?

Don J
2012-May-12, 07:41 PM
(snip).... but the point is that the steady state universe was eliminated as a possibility by HUDF and other such studies of the early universe.
Hmm It seem rather that the HUDF datas are showing some unexpected surprise...in favor of the steady state universe.

Evidence for a Non-Expanding Universe: Surface Brightness Data From HUDF

http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2
from the abstrac
Surface brightness data can distinguish between a Friedman-Robertson-Walker expanding universe and a non-expanding universe. For surface brightness measured in AB magnitudes per angular area, all FRW models, regardless of cosmological parameters, predict that surface brightness declines with redshift as (z+1)^-3, while any non-expanding model predicts that surface brightness is constant with distance and thus with z. High-z UV surface brightness data for galaxies from the Hubble Ultra Deep Field and low-z data from GALEX are used to test the predictions of these two models up to z=6. A preliminary analysis presented here of samples observed at the same at-galaxy wavelengths in the UV shows that surface brightness is constant, mu=kz^0.026+-0.15, consistent with the non-expanding model. This relationship holds if distance is linearly proportional to z at all redshifts, but seems insensitive to the particular choice of d-z relationship. Attempts to reconcile the data with FRW predictions by assuming that high-z galaxies have intrinsically higher surface brightness than low-z galaxies appear to face insurmountable problems. The intrinsic FUV surface brightness required by the FRW models for high-z galaxies exceeds the maximum FUV surface brightness of any low-z galaxy by as much as a factor of 40. Dust absorption appears to make such extremely high intrinsic FUV surface brightness physically impossible. If confirmed by further analysis, the impossibility of such high-surface-brightness galaxies would rule out all FRW expanding universe (big bang) models.

slang
2012-May-12, 08:03 PM
Hmm It seem rather that the HUDF datas are showing some unexpected surprise...in favor of the steady state universe.

Evidence for a Non-Expanding Universe: Surface Brightness Data From HUDF

http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2

How did you determine that this is a credible paper? Just by it being on arxiv? It doesn't seem to be published, there is no hint of peer-review, and it was apparently presented at something called "the First Crisis in Cosmology Conference".

TooMany
2012-May-12, 08:15 PM
What about the morphology of those galaxies? That doesn't depend on anybody's theoretical assumptions.


The HUDF shows that ... the early universe was filled with dwarf galaxies, but no fully formed galaxies like our Milky Way. -- source (http://www.spacetelescope.org/images/opo0428b/)


If the universe was in a "steady state," as you inexplicably seem to desire, some of those most distant galaxies would be fully formed. Well, sorry, but they're not.

You're citing some pretty old news here (2004). I think those conclusions have long since been dropped. I'd have to do some digging, but originally it appeared that the galaxies were irregular suggesting not fully formed but with the newer cameras they look more like local galaxies although they are interpreted to be much smaller, massive and as having star formation rates around 100X the local rate. Of course these conclusions are dependent upon the angular size and brightness expectations based on the expansion model.



There are no fully formed galaxies like the Milky Way back then.


Could you cite a more recent paper (not a news blurb) that makes that claim, particular for some other morphology (not size)?



By the way, the faintest objects in the HUDF are less than one four-billionth the brightness of stars that can be seen with the naked eye. This would tend to indicate that they are, you know, kinda far away. Or is the fact that things generally appear less luminous when they're farther away too much of a "theoretical assumption" for you?

Oh boy. You put words in my mouth and then make fun of them? Of course they are very far away where did you get the idea that I'm arguing that they are not?

slang
2012-May-12, 08:25 PM
You're citing some pretty old news here (2004).

Do you see how funny this is, right after you cite some 2005 paper? Oops, sorry, that wasn't you.

TooMany
2012-May-12, 08:37 PM
How did you determine that this is a credible paper? Just by it being on arxiv? It doesn't seem to be published, there is no hint of peer-review, and it was apparently presented at something called "the First Crisis in Cosmology Conference".

Would it get published? Such a heretical suggestion, contrary to everything we know? If you were the reviewer choosing amoung a pile of LCDM papers and this, would you publish this one? In addition there are papers suggesting that angular size is linear with z and that therefore evolution has to coincidentally result in this relationship. I believe the formula for size is proportional to 1/(1 + z)^-e where e is almost exactly one. You can find this in a recent mainstream paper discussing the morphology of galaxies at z~1.2.

Eric Lerner is a plasma physicist, not an astrophysicist by training. He has published a few other papers on the subject of astrophysics. Right now he is working on an underfunded Focus Fusion project that has produced the highest temperature plasma ever that I'm aware of. His paper on those fusion experiments has been published in a legitimate scientific journal.

TooMany
2012-May-12, 08:51 PM
Do you see how funny this is, right after you cite some 2005 paper? Oops, sorry, that wasn't you.

Let's not go to the level of silliness in arguments. My point about old news in that case is that it is superseded by newer observations. What 2005 paper are you talking about? Lerner's? Do you know of a paper that contradicts it? All that paper attempts to show is that luminosity is consistent with a Euclidean static universe and no evolution.

slang
2012-May-12, 09:13 PM
Would it get published?

Who knows? Let's not clutter this thread with that argument. The point is, it isn't, so we have no way of knowing if it was subjected to qualified peer review. This means it requires (at least some) expert knowledge to determine the validity of the paper. I believe you don't claim to be an expert, I certainly don't. How did Don J determine whether this is a valid paper or not?

Don J
2012-May-12, 10:49 PM
Who knows? Let's not clutter this thread with that argument. The point is, it isn't, so we have no way of knowing if it was subjected to qualified peer review. This means it requires (at least some) expert knowledge to determine the validity of the paper. I believe you don't claim to be an expert, I certainly don't. How did Don J determine whether this is a valid paper or not?
The datas in the paper(s) are available for all to see .... so the experts here can verify them .

here the 2009 paper ....the 2005 paper is described in post 28.

Tolman Test from z = 0.1 to z = 5.5: Preliminary results challenge the expanding universe model

http://search.arxiv.org:8081/details.jsp?qid=13368622905309a_nCnN_454274443&r=pdf/0906.4284v1

We performed the Tolman surface-brightness test for the expansion of the universe using a large UV dataset of disk galaxies in a wide range of redshifts (from 0.03 to 5.7). We combined data for low-z galaxies from GALEX observations with those for high-z objects from HST UltraDeep Field images. Starting from the data in publicly- available GALEX and UDF catalogs, we created 6 samples of galaxies with observations in a rest-frame band centered at 141 nm and 5 with data from one centered on 225 nm. These bands correspond, respectively, to the FUV and NUV bands of GALEX for objects at z = 0.1. By maintaining the same rest-frame wave-band of all observations we greatly minimized the effects of k-correction and filter transformation. Since SB depends on the absolute magnitude, all galaxy samples were then matched for the absolute magnitude range (-17.7 < M(AB) < -19.0) and for mean absolute magnitude. We performed homogeneous measurements of the magnitude and half-light radius for all the galaxies in the 11 samples, obtaining the median UV surface brightness for each sample. We compared the data with two models: 1) The LCDM expanding universe model with the widely-accepted evolution of galaxy size R prop H(z)-1 and 2) a simple, Euclidean, non-expanding (ENE) model with the distance given by d=cz/H0. We found that the ENE model was a significantly better fit to the data than the LCDM model with galaxy size evolution. While the LCDM model provides a good fit to the HUDF data alone, there is a 1.2 magnitude difference in the SB predicted from the model for the GALEX data and observations, a difference at least 5 times larger than any statistical error. The ENE provides a good fit to all the data except the two points with z>4.

TooMany
2012-May-12, 11:51 PM
How did Don J determine whether this is a valid paper or not?

What's the test that determines that? If it supports well-established mainstream conclusions then it's valid? Seriously it's a very simple paper that takes measured surface brightness at different z's and shows that they correlate well with certain assumptions: Euclidean space, linear z/distance relationship and no evolution of galaxies. Did you read it?

As far as I can no tell no one is interested in this coincidence. Oh well...

slang
2012-May-13, 01:13 AM
What's the test that determines that?

I don't know.. if I knew, I'd be eligible to do peer reviews in this field.


Did you read it?

Yes, I tried. I didnt get very far.

Tensor
2012-May-13, 05:34 AM
Seriously it's a very simple paper that takes measured surface brightness at different z's and shows that they correlate well with certain assumptions: Euclidean space, linear z/distance relationship and no evolution of galaxies. Did you read it?

Yeah, it's garbage. Lerner compares the LambdaCDM with the Euclidean, non- expanding (ENE) model. However, z values are very model specific. Lerner blithely uses the the z values in Hubble Ultra Deep Field (HUDF) images and catalogs and the GALEX Medium Imaging Survey (MIS), within the ENE model. He doesn't mention how the z values are arrived at in either of those catalogs. But I'm willing to bet that they used the normal method of using the FLRW metric. Which gets the z value by comparing the wavelength of light using the scale factor. Which measures the curvature of the universe, knowing it has a greater curvature earlier and a lesser curvature as the universe expands. Lerner can't use the z factor from an object that gets it's z factor in an expanding universe and think the z factor in a non expanding universe would be the same. But that's one of the assumptions. And while both models may have a linear z/distance relationship, the z/distance relationship does not correlate between models.

I'd also point out that the Universe cannot be Euclidean, as a Euclidean Universe is not Lorentz invariant. Which while you may want to argue on large scales(it's been done, unsuccessfully, I might add), it would also invalidate Quantum Field Theory.


As far as I can no tell no one is interested in this coincidence. Oh well...

Yeah, and to paraphrase Richard Feynman, I saw a license plate with my initials and three 5's in it.

slang
2012-May-13, 08:07 AM
Well, there you go. Thanks Tensor. Those are the kinds of things that make me wary when a paper is not published in a respected journal, when the author isn't a well known expert in the field, it's several years old but the paper reaches a staggering conclusion (which might well be trip-to-Oslo stuff), and yet a quick google mainly shows fringe sites like thunderbolt and journal of cosmology. I might have wasted hours going over this piece, trying to figure out the math, looking up references, words and symbols, and still miss something like valid data being used inappropriately.

Shaula
2012-May-13, 10:12 AM
Would it get published? Such a heretical suggestion, contrary to everything we know?

What's the test that determines that? If it supports well-established mainstream conclusions then it's valid?
Here we go again. The reviewer conspiracy... If a paper makes extraordinary claims then it will be examined closely, perhaps more closely than something more mainstream. That is usually because no reviewer is simultaneously skilled in every single model/interpretation of every physics theory ever and has to rad up on the topics. So the bar is slightly higher for new ideas. Which his as it should be. Many, many people generate many, many new ideas every day. If they were not pretty rigorously checked they'd be a huge noise source in physics.

And reviewers can and do pass the papers to people with more relevant background. Seen it happen many times. Had papers passed to me for this reason, then had to explain my case to the lead reviewer.

TooMany
2012-May-13, 04:33 PM
Yeah, it's garbage. Lerner compares the LambdaCDM with the Euclidean, non- expanding (ENE) model. However, z values are very model specific. Lerner blithely uses the the z values in Hubble Ultra Deep Field (HUDF) images and catalogs and the GALEX Medium Imaging Survey (MIS), within the ENE model. He doesn't mention how the z values are arrived at in either of those catalogs. But I'm willing to bet that they used the normal method of using the FLRW metric. Which gets the z value by comparing the wavelength of light using the scale factor. Which measures the curvature of the universe, knowing it has a greater curvature earlier and a lesser curvature as the universe expands. Lerner can't use the z factor from an object that gets it's z factor in an expanding universe and think the z factor in a non expanding universe would be the same. But that's one of the assumptions. And while both models may have a linear z/distance relationship, the z/distance relationship does not correlate between models.

I'd also point out that the Universe cannot be Euclidean, as a Euclidean Universe is not Lorentz invariant. Which while you may want to argue on large scales(it's been done, unsuccessfully, I might add), it would also invalidate Quantum Field Theory.

Yeah, and to paraphrase Richard Feynman, I saw a license plate with my initials and three 5's in it.

Well that's quite a refutation. So it's garbage. I thought z values are measurements of shift and nothing more and therefore not model dependent. But now you are saying that they are? Can you explain? If that is not what z values are that are reported in papers, then I think I'm back to square one trying to grasp cosmology. The z relationship to distance is model dependent. The model he chooses for comparison is "a simple, Euclidean, nonexpanding (ENE) model with the distance given by d=cz/H0". I guess I don't understand your objection.

TooMany
2012-May-13, 04:47 PM
If a paper makes extraordinary claims then it will be examined closely, perhaps more closely than something more mainstream.

The claim is not extraordinary per se, it is simply pointing out that certain assumptions are consistent with certain observations. You don't have to believe any of those assumptions. He even allows that more data is needed to see if the relationship is born out. The relationship does not prove anything by itself. The question is whether the paper is correct about the relationship. If you react to at as an attempt to overturn current theory and deny the relationship on that basis, then you are being intellectually dishonest if the relation does in fact exist. It could exist even within the context of current theory by coincidence.

Who has examined this paper? Originally published in 2005 I can find no citation. Nothing that denies the claim for example.

parejkoj
2012-May-13, 04:53 PM
Eric Lerner is pretty much always wrong about cosmology. That this work was not published in a peer-reviewed journal is entirely unsurprising, considering its poor quality. That it is uncited is also unsurprising: Lerner is ignored practicing cosmologists, with good reason.

I don't know how he did the calculations that went into Figure 1, but cz/H_0 != Integral(c dt/a(t)) in the concordance cosmology. His plot (minus the supernova points) should look like this:

16872

This is not "[an] agreement ... better than 0.3 mag over the whole range of redshift up to z =5..." In fact, here's how different they are across the redshift range:

16873

I would call his choice of plotting vs. log(z) rather misleading as well, but that doesn't matter if he can't get the numbers right. If he can't do this simple calculation correctly (granted, its not an analytic integral, but that's what computers are for), what's the point of my looking at the rest of it?

He also assumes that the high redshift galaxies are similar enough to the low redshift galaxies that one can do a direct comparison of their surface brightnesses. This is not at all a reasonable assumption in the standard cosmology, nor is it borne out by observations.

Shaula
2012-May-13, 06:06 PM
Who has examined this paper? Originally published in 2005 I can find no citation. Nothing that denies the claim for example.
Most working scientists have better things to do with their time that write papers refuting unpublished papers.

If it made no extraordinary claims and still has not been published then the most logical assumption is: bad paper.

Tensor
2012-May-13, 06:17 PM
Well that's quite a refutation. So it's garbage. I thought z values are measurements of shift

Measurement of shift are not z values. For instance, the blue-green Hydrogen line is at 486 nm, in a rest frame. If, looking at the spectrum of an object, that line now shows it is at ~537nm. That object is showing a redshift of ~51 nm. That measurement does not depend on any model as that is a straight observation. You now have to take that observation and convert it. That is where the model comes in.


and nothing more and therefore not model dependent. But now you are saying that they are? Can you explain?

However, what that shift represents IS highly model dependent. Is it a straight doppler shift? How about a gravitational shift? Or could it be a cosmological shift? For an expanding universe, it is normally given by comparing α, the scale factor (http://en.wikipedia.org/wiki/Scale_factor_(Universe)), 1 + z =α now/α then. Almost all z numbers are based on an expanding universe, and so use a scale factor.


If that is not what z values are that are reported in papers, then I think I'm back to square one trying to grasp cosmology. The z relationship to distance is model dependent. The model he chooses for comparison is "a simple, Euclidean, nonexpanding (ENE) model with the distance given by d=cz/H0". I guess I don't understand your objection.

What is the scale factor of the z-value in a non-expanding universe? Remember, simplified, the scale factor is a value for the radius of curvature for the universe. Earlier times have more curvature, latter times, with expansion, have less.
How does he convert the z value, based on the expanding universe, with curvature defined by the scale factor, to one based on that z value in a Non-expanding universe? Is it a straight doppler interpretation? But, we know that a straight doppler interpretation doesn't work. Because around z = 1.5, the doppler shows recession at greater than c. Unless you can explain to us the straight doppler of the galaxies he uses with say around z > 1.5. We don't know, he doesn't specify. But we do know he can't be using a FLRW metric for his ENE universe.

And, yeah, how about explaining how that Euclidean universe works, since it's not Lorentz Invariant.

I would also point out that he doesn't specify the exact objects he used. He gives their averages, means, etc. But never a list of the exact objects.

Don J
2012-May-13, 07:00 PM
However, what that shift represents IS highly model dependent. Is it a straight doppler shift? How about a gravitational shift? Or could it be a cosmological shift? For an expanding universe, it is normally given by comparing α, the scale factor (http://en.wikipedia.org/wiki/Scale_factor_(Universe)), 1 + z =α now/α then. Almost all z numbers are based on an expanding universe, and so use a scale factor.
What is the scale factor of the z-value in a non-expanding universe?

The model dependent factor is taken into account as you can read in chapter 1 in the 2005 paper.
Chapter 1-surface brightness test ...
http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2

Don J
2012-May-13, 07:12 PM
Eric Lerner is pretty much always wrong about cosmology. That this work was not published in a peer-reviewed journal is entirely unsurprising, considering its poor quality. That it is uncited is also unsurprising: Lerner is ignored practicing cosmologists, with good reason.

I don't know how he did the calculations that went into Figure 1, but cz/H_0 != Integral(c dt/a(t)) in the concordance cosmology. His plot (minus the supernova points) should look like this:

16872



The fig 1 you are talking about is from the 2009 paper
http://search.arxiv.org:8081/details.jsp?qid=13368622905309a_nCnN_454274443&r=pdf/0906.4284v1

Your plot is in fact confirming what he said, (ie) that the data fits the Non expanding universe theory. Read what is writed under fig 1 for details.
http://www.bautforum.com/attachment.php?attachmentid=16872&d=1336927243

Tensor
2012-May-13, 07:49 PM
The model dependent factor is taken into account as you can read in chapter 1 in the 2005 paper.
Chapter 1-surface brightness test ...
http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2

Actually, no it's not. It talks about the angular size. For FLRW θ=k(z+1)/d and for Non Expanding θ=k/d. Can you point out where the changes to z are made between models? Then, it goes on to state that the θ-z relationship holds.... assuming d=cz/H. How did he convert the 1 + z redshifts given on the spectra to z in the formula? What does the redshift mean in his non-expanding universe, as he never mentions it.

How about the Euclidean Universe not being Lorentz invariant?

Do you have a location for objects he used in the paper?

TooMany
2012-May-13, 08:35 PM
I don't know how he did the calculations that went into Figure 1, but cz/H_0 != Integral(c dt/a(t)) in the concordance cosmology. His plot (minus the supernova points) should look like this:

16872

This is not "[an] agreement ... better than 0.3 mag over the whole range of redshift up to z =5..." In fact, here's how different they are across the redshift range:

16873


He is not claiming that cz/H_0 is concordance cosmology, it's an assumption that he is making for comparison and is specifically not the concordance model.

OK, just to be sure I understand correctly, his plot for LCDM is entirely wrong and he must be using the wrong mathematics. It's too bad that everybody is too busy to tell him that. Consider this, that such things can mislead the public, so maybe it is worth someone actually writing a paragraph to respond to it publicly. After all, the people on this forum are constantly correcting people on their misconceptions.


I would call his choice of plotting vs. log(z) rather misleading as well...


Why is it misleading? I'm guessing he chose it because it's a linear relationship under his assumptions.



He also assumes that the high redshift galaxies are similar enough to the low redshift galaxies that one can do a direct comparison of their surface brightnesses. This is not at all a reasonable assumption in the standard cosmology, nor is it borne out by observations.

He explicitly makes that assumption which is the entire point of the paper - no evolution. It says that right at the beginning. Whether that assumption is correct does not directly bear on what he seems to be trying to illustrate - a relationship. The correctness of the assumption is a separate issue. Science has been built on discovering mathematical relationships among things (e.g. the motions of the planets) and then trying to formulate a theory that predicts those relationships.

I'll accept your judgement for the moment that the paper is completely incorrect in it's representation of concordance cosmology. But may I make a small point? When someone points out a relationship of any kind in observations, they are not under any obligation to make that relationship fit with some existing model or other evidence. For example the Tully-Fisher relationship is obversed but I don't think we can state that it is fully understood. It's just a relationship based on observations. Whether an observation seems to support an existing theory or not does not change that observation.

Strangely he says this at the end of the paper "The author wishes to acknowledge the large contributions to the analysis of this data of Renato Falomo and Riccardo Scarpa." A quick check shows that those folks (unless he is referring to others who coincidentally have the same names) are coauthors of published papers in astrophysics. So perhaps he's fibbing and they really did not check his analysis or they don't understand LCDM either. I noticed that they have some association with non-mainstream ideas (e.g. MOND).

Jeff Root
2012-May-13, 08:38 PM
However, z values are very model specific.
I was very surprised when I read this, too.
It isn't what you meant, is it? The z value is not at
all model-specific. It is the interpretation of why the
z value is whatever it is that is model specific.



Lerner blithely uses the the z values in Hubble Ultra Deep
Field (HUDF) images and catalogs and the GALEX Medium
Imaging Survey (MIS), within the ENE model. He doesn't
mention how the z values are arrived at in either of those
catalogs.
I can't imagine how that would matter.



But I'm willing to bet that they used the normal method
of using the FLRW metric. Which gets the z value by
comparing the wavelength of light using the scale factor.
That makes no sense to me. Can't they identify any
spectral lines? Are they depending on something other
than identified spectral lines to determine z?

-- Jeff, in Minneapolis

TooMany
2012-May-13, 08:58 PM
However, what that shift represents IS highly model dependent. Is it a straight doppler shift? How about a gravitational shift? Or could it be a cosmological shift? For an expanding universe, it is normally given by comparing α, the scale factor (http://en.wikipedia.org/wiki/Scale_factor_(Universe)), 1 + z =α now/α then. Almost all z numbers are based on an expanding universe, and so use a scale factor.


In bold above is the definition of z. It is just a measurement of the red shift. These numbers are not "based on an expanding universe", they are pure observations of shift in wavelength of known spectral lines. I don't understand the purpose of your last sentence above.



How does he convert the z value, based on the expanding universe, with curvature defined by the scale factor, to one based on that z value in a Non-expanding universe? Is it a straight doppler interpretation? But, we know that a straight doppler interpretation doesn't work. Because around z = 1.5, the doppler shows recession at greater than c. Unless you can explain to us the straight doppler of the galaxies he uses with say around z > 1.5. We don't know, he doesn't specify. But we do know he can't be using a FLRW metric for his ENE universe.

I not sure what you're getting at here. He doesn't offer any explanation of his hypothetical assumptions, he simply states them. He uses d=cz/H_0 as an assumption which is obviously not the same as the concordance model. He does claim any physical reason for it.



I would also point out that he doesn't specify the exact objects he used. He gives their averages, means, etc. But never a list of the exact objects.

He states the catalogs he used and his selection criteria in "3. Data analysis and results". This is quite common in papers. Do you seriously object to it?

parejkoj
2012-May-13, 09:09 PM
He is not claiming that cz/H_0 is concordance cosmology, it's an assumption that he is making for comparison and is specifically not the concordance model.

I understood that. But he made a plot with his redshift/distance relation (cz/H_0) and the LCDM redshift/distance relation, and at least one of the two things on the plot is wrong, as demonstrated by my plot. The way he plotted it makes it hard to see which one he did incorrectly.

Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable. If you don't believe me, you can download the supernova data (http://supernova.lbl.gov/union/) and try it yourself.

In fact, his non-expanding cosmology is ruled out quite nicely by the supernova data. Seriously: download the data from the Union2 team, plot z vs. mu, and then overplot z vs. mu for LCDM, cz/H_0, and whatever other cosmology you prefer. You've done a lot of accusing of astronomers of not doing their homework on these threads, but I haven't seen you do any actual calculations yourself.


OK, just to be sure I understand correctly, his plot for LCDM is entirely wrong and he must be using the wrong mathematics. It's too bad that everybody is too busy to tell him that. Consider this, that such things can mislead the public, so maybe it is worth someone actually writing a paragraph to respond to it publicly. After all, the people on this forum are constantly correcting people on their misconceptions.

Such things are only "misleading to the public" if the public uncritically reads every arxiv paper. As Shaula says above, "Most working scientists have better things to do with their time that write papers refuting unpublished papers." Of course, some of them do bother to post on message boards, but...

Lerner has been consistently wrong for so many years that no one even bothers responding to him these days (some did in the 90's). There's a point at which responding just provides a semblance of legitimacy to silly ideas, and one should just walk away.


He explicitly makes that assumption which is the entire point of the paper - no evolution. It says that right at the beginning. Whether that assumption is correct does not directly bear on what he seems to be trying to illustrate - a relationship. The correctness of the assumption is a separate issue.

And the assumption is patently not correct, from any analysis of z>~1 galaxy photometry. Most of the galaxies that exist today have few to no analogs at high redshift, and vice versa. Here's a recent place to start (http://adsabs.harvard.edu/abs/2011ApJ...743L..15V).

Tensor
2012-May-13, 09:16 PM
I was very surprised when I read this, too.
It isn't what you meant, is it? The z value is not at
all model-specific. It is the interpretation of why the
z value is whatever it is that is model specific.

Read my reply. A non-expanding universe cannot use a scale factor to get the z value, as there is nothing to compare (unless you want to note that the z value is 1). Conversely, in the current mainstream model, a straight doppler z value is incorrect out past ~ z = 1.5. Model specific.


I can't imagine how that would matter.

Well, he uses the z values, without mentioning what model those values were taken from.


That makes no sense to me. Can't they identify any
spectral lines? Are they depending on something other
than identified spectral lines to determine z?

-- Jeff, in Minneapolis

Again, he never mentions the spectra, he talks about z values he used and the different BANDS that were compared. But there are no specifics about how the z values were found.

TooMany
2012-May-13, 09:47 PM
I understood that. But he made a plot with his redshift/distance relation (cz/H_0) and the LCDM redshift/distance relation, and at least one of the two things on the plot is wrong, as demonstrated by my plot. The way he plotted it makes it hard to see which one he did incorrectly.

Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable. If you don't believe me, you can download the supernova data (http://supernova.lbl.gov/union/) and try it yourself.


Please examine Figure 4 here (http://www.pnas.org/content/101/1/8.figures-only). This is plotted the same way as Lerner's Figure 1 and it looks identical to me. It's a straight line!

If you're still laughing, can you explain why?

parejkoj
2012-May-13, 09:52 PM
Please examine Figure 4 here (http://www.pnas.org/content/101/1/8.figures-only). This is plotted the same way as Lerner's Figure 1 and it looks identical to me. It's a straight line!

If you're still laughing, can you explain why?

Ah, yes, the "what's the problem, it looks like a FOO to me" defense. We don't do chi-by-eye in astronomy. At least, we try not to. I think that makes up a large part of your (and certainly most ATM proponents') problems.

I'm just going to repeat what I wrote before. If you have questions about how to do it, you can start a thread here on BAUT, and people will be happy to assist you. I've already given you a link to the data, and some hints about how to perform the necessary calculations.


...download the data from the Union2 team, plot z vs. mu, and then overplot z vs. mu for LCDM, cz/H_0, and whatever other cosmology you prefer. You've done a lot of accusing of astronomers of not doing their homework on these threads, but I haven't seen you do any actual calculations yourself.

TooMany
2012-May-13, 10:27 PM
Ah, yes, the "what's the problem, it looks like a FOO to me" defense. We don't do chi-by-eye in astronomy. At least, we try not to. I think that makes up a large part of your (and certainly most ATM proponents') problems.


What kind of response is that? You said "Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable."

His plot is virtually identical to the plot I referenced. Lerner may have misrepresented LCDM (at least so you say). But his graph of supernova data matches that of Robert P. Kirshner (Harvard–Smithsonian Center for Astrophysics).

I don't need chi to tell me that it's a straight line. The scatter is fairly small and you can run a ruler straight through it. It's straight as can be, considering the amount of scatter.

Let's stick to this point. Is Kirsher's graph also laughable or not? Your credibility in my mind is in doubt.

parejkoj
2012-May-13, 11:17 PM
I don't need chi to tell me that it's a straight line. The scatter is fairly small and you can run a ruler straight through it. It's straight as can be, considering the amount of scatter.

Congratulations, you've discovered that everything looks like a straight line on a log/log plot!

Make the plot yourself, using the data I linked, and the theoretical curves from each cosmology, in the way I described: z vs. mu, not log(z) vs. mu. The latter would work, but the difference would be less clear. That's one problem with log/log plots. They have their uses, but in this case it isn't really necessary.

I don't see much point in arguing this with you, unless you go and make the plot yourself. It's clear that you don't understand what Lerner's done wrong (have you ever integrated the Friedman equation?), and until you make an effort to do so on your own, we're not going to get anywhere.


Let's stick to this point. Is Kirsher's graph also laughable or not? Your credibility in my mind is in doubt.

Oh, you doubt my credibility? Oh my, whatever shall I do. [/snark]

I gave you two plots above showing the difference between the LCDM and Lerner cosmology z vs. mu values. The first plot is quite different from Figure 1 in his paper, and the second plot showed that his claims regarding his cosmology and the supernova data were strongly in doubt. I pointed you toward data from which you could make a plot to clear up this matter yourself, and gave you some suggestions about how to do so. I even suggested that if you have trouble doing so, people here might be able to help you.

I don't want you to argue with me about it, I want you to make the plot and see for yourself. After all, I'm just some random schmoe on the internet... :whistle:

TooMany
2012-May-14, 12:03 AM
Congratulations, you've discovered that everything looks like a straight line on a log/log plot!

Make the plot yourself, using the data I linked, and the theoretical curves from each cosmology, in the way I described: z vs. mu, not log(z) vs. mu. The latter would work, but the difference would be less clear. That's one problem with log/log plots. They have their uses, but in this case it isn't really necessary.


Let's get back to the subject of Lerner's paper. Here's part of what he claims in that first figure:



For this study, we assume that the relationship d= cz/H0 holds for all z. For a non-expanding model, M can be derived from the apparent magnitude m (in the AB system) using the relation: M - m = 5 -5Log(cz/H0).


So his claim is that M-m is linear with log(cz/H_0). His graph shows that SN closely follow this relationship, as close as the scatter allows (apparently). I found another source that precisely duplicates his graph. Aside from your statement that his graph is wrong for the LCDM prediction, what exactly is wrong with his graph that makes it laughable? Don't tell me to draw some graph. Please answer the question. What is wrong with his statement and the graph which certainly looks to be correct (aside from LCDM calculations)?

Are you telling me that data (even with that much scatter) is really not straight but definitely slightly curved? Please clarify.

parejkoj
2012-May-14, 01:15 AM
Are you telling me that data (even with that much scatter) is really not straight but definitely slightly curved? Please clarify.

I'm telling you to make the plot yourself. My "telling you" anything isn't going to help you learn what's going on here; you figuring it out on your own is.

As I said, Lerner is pretty much always wrong about cosmology. Looking at his plot isn't going to provide you with anything useful. Make the plot, then we'll talk. If you don't know how, ask and we'll help you.

Reality Check
2012-May-14, 01:25 AM
The datas in the paper(s) are available for all to see .... so the experts here can verify them .

here the 2009 paper ....the 2005 paper is described in post 28.

Tolman Test from z = 0.1 to z = 5.5: Preliminary results challenge the expanding universe model

http://search.arxiv.org:8081/details.jsp?qid=13368622905309a_nCnN_454274443&r=pdf/0906.4284v1

Unfortunately this "paper" fails some of the criteria that a skeptical person would apply:

It is not a paper! It is a conference presentation as is the 2005 "paper".
The author's area of expertise is plasma physics and here he is analysing astronomical data. This makes it more likely that his analysis is wrong.
It is a single author presentation. Today, major breakthroughs in science are rarely single author efforts.


The best way to see that this is a simplistic and thus probably flawed presentation is to look at what astronomers have done, e.g. the 4 papers by Sandage and Lubin in 2001:
The Tolman Surface Brightness Test for the Reality of the Expansion. I. Calibration of the Necessary Local Parameters (http://arxiv.org/abs/astro-ph/0102213)
The Tolman Surface Brightness Test for the Reality of the Expansion. II. The Effect of the Point-Spread Function and Galaxy Ellipticity on the Derived Photometric Parameters (http://arxiv.org/abs/astro-ph/0102214)
The Tolman Surface Brightness Test for the Reality of the Expansion. III. HST Profile and Surface Brightness Data for Early-Type Galaxies in Three High-Redshift Clusters (http://arxiv.org/abs/astro-ph/0106563)
The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies (http://arxiv.org/abs/astro-ph/0106566)

We conclude that the Tolman surface brightness test is consistent with the reality of the expansion. We have also used the high-redshift HST data to test the ``tired light'' speculation for a non-expansion model for the redshift. The HST data rule out the ``tired light'' model at a significance level of better than 10 sigma.
and an update in 2009:
The Tolman Surface Brightness Test for the Reality of the Expansion. V. Provenance of the Test and a New Representation of the Data for Three Remote HST Galaxy Clusters (http://arxiv.org/abs/0905.3199)

Reality Check
2012-May-14, 01:49 AM
All that paper attempts to show is that luminosity is consistent with a Euclidean static universe and no evolution.
The last part is the bit that I find most incredible about the paper. Lerner is presenting himself as an astronomer and yet he ignores the physics that stars and galaxies evolve!
Reading the Sandage and Lubin fourth paper shows that the data matches an expanding universe even with just the passive evolution by main sequence burn-down in the HR diagram as a function of time. Using more sophisticated models of galaxy evolution makes the match better.

parejkoj
2012-May-14, 01:50 AM
Unfortunately this "paper" fails some of the criteria that a skeptical person would apply:

It is not a paper! It is a conference presentation as is the 2005 "paper".
The author's area of expertise is plasma physics and here he is analysing astronomical data. This makes it more likely that his analysis is wrong.
It is a single author presentation. Today, major breakthroughs in science are rarely single author efforts.


I'd definitely take issue with your last bullet (though I am certainly fond of large collaborations), and some issue with your second.

Though you are correct that "major breakthroughs ... are rarely single author efforts", your citations of Allan Sandage's work shows that single author papers can be very thorough. A long author list doesn't guarantee quality work either: Arp's group has produced a few papers in the past decade(ish) with a half a dozen authors or so. That doesn't mean they're any good.

Whether someone is an "expert" in a subject can also sometimes be hard to immediately judge. In Lerner's case, it's obvious to those who are experts that he lacks a lot of relevant knowledge. But that doesn't mean that someone trained in plasma physics can't do good cosmology.

Your first point is certainly robust, if there are no related peer-reviewed publications. Plenty of conference proceedings contain useful information, but they usually refer to, or are followed by, papers submitted for review.

Don J
2012-May-14, 01:53 AM
The last part is the bit that I find most incredible about the paper. Lerner is presenting himself as an astronomer and yet he ignores the physics that stars and galaxies evolve!

Not sure but i think Lerner is rather saying that Stars and Galaxies evolve even in a non expanding universe model.

Jeff Root
2012-May-14, 02:09 AM
I was very surprised when I read this, too.
It isn't what you meant, is it? The z value is not at
all model-specific. It is the interpretation of why the
z value is whatever it is that is model specific.
Read my reply. A non-expanding universe cannot
use a scale factor to get the z value, as there is
nothing to compare (unless you want to note that
the z value is 1). Conversely, in the current
mainstream model, a straight doppler z value is
incorrect out past ~ z = 1.5. Model specific.
The only things to compare that I know of are spectral
lines in light from the distant object and spectral lines
in the lab. I don't see where any model is involved.




I can't imagine how that would matter.
Well, he uses the z values, without mentioning
what model those values were taken from.
Why would they come from a model rather than
from measurements?




That makes no sense to me. Can't they identify any
spectral lines? Are they depending on something other
than identified spectral lines to determine z?
Again, he never mentions the spectra, he talks about
z values he used and the different BANDS that were
compared. But there are no specifics about how the
z values were found.
I may be misunderstanding, but it seems to say in
the quote in post #35 above that the z values were
taken from the GALEX and UDF catalogs. They would
be where to get specifics on how the spectra were
taken and lines measured.

-- Jeff, in Minneapolis

Reality Check
2012-May-14, 02:18 AM
I'd definitely take issue with your last bullet (though I am certainly fond of large collaborations), and some issue with your second.

Actually only the last paper is only by Allan Sandage, the rest are coauthored by Lubin. But you are right - the presence of a single author is just an indication that a paper should be looked at more skeptically.

Reality Check
2012-May-14, 02:19 AM
Not sure but i think Lerner is rather saying that Stars and Galaxies evolve even in a non expanding universe model.
Fairly sure that Lener's ENE model assumes that galaxies do not evolve (as TooMany stated) and so is wrong.

ETA: He also ignores galaxy evolution for the LCDM model (he mentions "galaxy size evolution"). This invalidates the fits he makes to that model and thus the presentation.

Don J
2012-May-14, 03:26 AM
Fairly sure that Lener's ENE model assumes that galaxies do not evolve (as TooMany stated) and so is wrong.

In the 2005 paper page 12 in the Discussion chapter Lerner say:"...plasma cosmology which assume an evolving universe without an origin in time ..."



ETA: He also ignores galaxy evolution for the LCDM model (he mentions "galaxy size evolution"). This invalidates the fits he makes to that model and thus the presentation.
You mean probably the chapter 3.1 in page 8 - Test of the evolution hypothesis -

Well ...I think that his objection in regard to the way ie(the assumption) the LCDM model have made their basis on , merits attention.

Reality Check
2012-May-14, 04:55 AM
In the 2005 paper page 12 in the Discussion chapter Lerner say:"...plasma cosmology which assume an evolving universe without an origin in time ..."

Nothing to do with what I am talking about.
Nowhere in either paper does Lerner state anything like "this is the model of evolving galaxies that I am using".
Thus he is ignoring the astronomy that stars evolve, galaxies evolve and so the surface brightness of galaxies changes with time. Ignoring this invalidates the Tolman surface brightness test (something the wikipedia article (http://en.wikipedia.org/wiki/Tolman_surface_brightness_test) does not mention).

You need to read the the Sandage and Lubin fourth paper to see the real astronomy. They get a good match with just the passive evolution by main sequence burn-down in the HR diagram as a function of time. Using more sophisticated models of galaxy evolution makes the match better.


You mean probably the chapter 3.1 in page 8 - Test of the evolution hypothesis
Well ...I think that his objection in regard to the way ie(the assumption) the LCDM model have made their basis on , merits attention.
The only objection is the rather ignorant statement "They have consistently explained this discrepancy as a consequence of galaxy evolution.".
Sandage and Lubin know that the surface brightness of galaxies changes with time and include this in their model. It is not used to explain any discrepancy. It is a physical fact that needs to be included in the model. The only issue is how to include this. With the passive evolution by main sequence burn-down in the HR diagram as a function of time they get a good match. Using more sophisticated models of galaxy evolution makes the match better.

Don J
2012-May-14, 05:11 AM
In the 2005 paper page 12 in the Discussion chapter Lerner say:"...plasma cosmology which assume an evolving universe without an origin in time ..."
Nothing to do with what I am talking about.
Nowhere in either paper does Lerner state anything like "this is the model of evolving galaxies that I am using".(#)

Are you saying that Lerner is not a Plasma Universe proponent ?



Thus he is ignoring the astronomy that stars evolve, galaxies evolve and so the surface brightness of galaxies changes with time.
Ignoring this invalidates the Tolman surface brightness test (something the wikipedia article (http://en.wikipedia.org/wiki/Tolman_surface_brightness_test) does not mention).

The only objection is the rather ignorant statement "They have consistently explained this discrepancy as a consequence of galaxy evolution.".
Sandage and Lubin know that the surface brightness of galaxies changes with time and include this in their model. It is not used to explain any discrepancy. It is a physical fact that needs to be included in the model. The only issue is how to include this. With the passive evolution by main sequence burn-down in the HR diagram as a function of time they get a good match. Using more sophisticated models of galaxy evolution makes the match better.


The objection made by Lerner is that a test at UV wavelengths is the real deal to test galaxies evolution. = ( This is the model he use )

chapter 3.1 page 8 in the 2005 paper.
http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2

TooMany
2012-May-14, 05:55 AM
I'm telling you to make the plot yourself. My "telling you" anything isn't going to help you learn what's going on here; you figuring it out on your own is.

As I said, Lerner is pretty much always wrong about cosmology. Looking at his plot isn't going to provide you with anything useful. Make the plot, then we'll talk. If you don't know how, ask and we'll help you.

No way! You are the one who declared that Figure 1 is absolutely wrong ("laughable"). It's your burden to explain why. If you cannot, I can only assume that you're blowing smoke. (I'd rather not reach that conclusion.)

parejkoj
2012-May-14, 02:38 PM
No way! You are the one who declared that Figure 1 is absolutely wrong ("laughable"). It's your burden to explain why. If you cannot, I can only assume that you're blowing smoke. (I'd rather not reach that conclusion.)

I didn't claim the figure itself was laughable:


Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable.

I suppose I shouldn't have said "laughable," but rather "completely and utterly pants-on-fire (http://static.politifact.com.s3.amazonaws.com/rulings%2Ftom-pantsonfire.gif) false," which would be wildly obvious to you if you made said plot. I'm asking you to make your own version of the plot as a learning exercise (I already made it to confirm what it looks like).

In addition, the BAUT forum rules say that proponents of against-the-mainstream (ATM) ideas have to defend them. This has become a thread supporting an ATM idea (plasma cosmology was actually declared off limits (http://www.bautforum.com/showthread.php/45529-Read-this-first-re-posting-quot-Electric-Universe-quot-ideas-here) on BAUT several years ago!), so it's up to you (and Don J) to defend it. One way to "defend" it would be to make the plot I described. Though that wouldn't actually help your case, as you'd see if you just made the dang plot.

[edit to add]: My suggestion to make the plot goes to anyone reading this thread. It's a nice example of the predictive power of the standard cosmology: take cosmological parameters derived from WMAP, compute the redshift vs. distance modulus curve, overplot supernova points. One can also then plot the z vs. mu curve for other cosmologies for comparison. The calculations involved are not that difficult (you have to do a numeric integral for LCDM), and the data is all publicly available. As I said, if you want help doing this, start a BAUT thread.

TooMany
2012-May-14, 03:23 PM
Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable.


If by mu~cz/H_0 you mean that mu is directly proportion to z, then I don't see where he said that. What he actually hypothesized was this relationship:

mu = = 5-5Log(cz/H0)

which he derived from this assumption:

d = cz/H0



In addition, the BAUT forum rules say that proponents of against-the-mainstream (ATM) ideas have to defend them. This has become a thread supporting an ATM idea (plasma cosmology was actually declared off limits (http://www.bautforum.com/showthread.php/45529-Read-this-first-re-posting-quot-Electric-Universe-quot-ideas-here) on BAUT several years ago!), so it's up to you (and Don J) to defend it. One way to "defend" it would be to make the plot I described. Though that wouldn't actually help your case, as you'd see if you just made the dang plot.

If this plot is so important why don't you simply give us a link to it and then you can show us what's amiss in the paper?

Hold your horses on the ATM stoning. This paper was cited in a discussion. Nobody claimed that they could back it up or that they were prepared to defend it's hypothetical assumptions. You trashed it. It is your problem to show where the paper is incorrect. It's your job to defend your own accusations.

Bear in mind that the paper only makes a claim about a fit of observations to a relationship. If you want to say it's wrong then you have to demonstrate the specific errors in the paper. His assumptions are just assumptions. Attacking those is meaningless because the paper does not even attempt to support those assumptions. It only claims to show that, under those assumptions, observations of surface brightness closely follow the relationship derived from those assumptions.

Swift
2012-May-14, 03:24 PM
This thread has become long and involved enough that it is no longer appropriate for Q&A, so I have moved it from there to Astronomy.

I will also remind various members that if they use this thread to sneak in ATM ideas, even if they can reference them to published papers, that they will be severely infracted. Just because someone in a published article agrees with your non-mainstream idea, doesn't relieve you of the ATM requirements. Consider that an official warning.

Swift
2012-May-14, 03:26 PM
In addition, the BAUT forum rules say that proponents of against-the-mainstream (ATM) ideas have to defend them. This has become a thread supporting an ATM idea (plasma cosmology was actually declared off limits (http://www.bautforum.com/showthread.php/45529-Read-this-first-re-posting-quot-Electric-Universe-quot-ideas-here) on BAUT several years ago!), so it's up to you (and Don J) to defend it. One way to "defend" it would be to make the plot I described. Though that wouldn't actually help your case, as you'd see if you just made the dang plot.


Hold your horses on the ATM stoning. This paper was cited in a discussion. Nobody claimed that they could back it up or that they were prepared to defend it's hypothetical assumptions. You trashed it. It is your problem to show where the paper is incorrect. It's your job to defend your own accusations.

I will also remind everyone not to play moderator. If you believe someone is posting something inappropriate, then report it and let the moderators take care of it. Next person who does this again will get an infraction.

parejkoj
2012-May-14, 06:27 PM
If by mu~cz/H_0 you mean that mu is directly proportion to z, then I don't see where he said that. What he actually hypothesized was this relationship:

mu = = 5-5Log(cz/H0)

which he derived from this assumption:

d = cz/H0


I'm aware of what he wrote. Sorry if my shorthand confused you. The plots (which you seem unable or unwilling to attempt to make yourself) I made in this post (http://www.bautforum.com/showthread.php/132173-Creation-of-new-galaxies?p=2017293#post2017293) used mu=5log(cz/H0)-5 and mu=5log(D_L)-5, where D_L is the luminosity distance at each redshift given Omega_Lambda=0.73 and Omega_M=0.27, both taking H0=100km/s/Mpc.

Again, you keep poking at things I say without bothering to look at the data yourself. Why is that? As I said above, I'm just some random schmoe on the internet. You don't have any particular reason to listen to what I say. You should be listening to the data, and I've shown you where to get it, and suggested how to do the relevant calculations. If you do that, it should become amply clear why I've said Lerner gets this completely wrong. You'll learn a lot more that way than if I just try to explain it to you as I did when making those two plots.

TooMany
2012-May-14, 07:43 PM
I'm aware of what he wrote. Sorry if my shorthand confused you. The plots (which you seem unable or unwilling to attempt to make yourself) I made in this post (http://www.bautforum.com/showthread.php/132173-Creation-of-new-galaxies?p=2017293#post2017293) used mu=5log(cz/H0)-5 and mu=5log(D_L)-5, where D_L is the luminosity distance at each redshift given Omega_Lambda=0.73 and Omega_M=0.27, both taking H0=100km/s/Mpc.

Again, you keep poking at things I say without bothering to look at the data yourself. Why is that? As I said above, I'm just some random schmoe on the internet. You don't have any particular reason to listen to what I say. You should be listening to the data, and I've shown you where to get it, and suggested how to do the relevant calculations. If you do that, it should become amply clear why I've said Lerner gets this completely wrong. You'll learn a lot more that way than if I just try to explain it to you as I did when making those two plots.

So you are taking issue with his representation of the theoretical LCDM magnitude/red-shift relationship? Your first plot shows how LCDM theory is different from what he is claiming in his Figure 1 where he states "obtained from the concordance cosmology with Omega_M=0.26 and Omega =0.76 (dashed line)". If that's the plot you want me to make, I don't know how, but I can try to find out.

You have no issue with his claim that mu=5log(cz/H0)-5 closely matches the SN data. Correct?

TooMany
2012-May-14, 10:07 PM
Again, you keep poking at things I say without bothering to look at the data yourself..

OK, I've went on a hunt for LCDM graphs and I think I have verified that his graph for the LCDM curve is not quite correct. If you look at the highest point that he plots (around log(z) = 0.25), mu should be about 45, not 44.5 as he shows. Also this statement:


It is remarkable that this relation gives very similar values (see Figure 1) to those computed using the concordance cosmology. The agreement is better than 0.3 mag over the whole range of redshift up to z =5 and for most of the range, including nearly the entire range covered by supernova observations, it is better than 0.1 mag.

looks to be incorrect. The agreement with LCDM could not be that good to z=5 and, over the range in his figure, the difference is more like 0.5 than 0.1. So yes this appears to be a mistake. However, I would also point out it has very little to do with the rest of the paper. It appears that he was trying to show that the models are quite similar at low z (which they are, but not as similar as he suggests) so that high z measurements are needed to resolve the surface brightness issue.

He goes on to show in figure 2 what he claims to be the surface brightness prediction from LCDM for a constant intrinsic surface brightness. Do you also take issue with that graph? Then he plots some points from his sample to show the difference between the LCDM prediction (for a constant intrinsic surface brightness) and observations. Finally he shows the same differences with his assumptions, apparently showing a better match. What do you take issue with here?

Reality Check
2012-May-14, 11:28 PM
Are you saying that Lerner is not a Plasma Universe proponent ?

No I am not. Read what I wrote - no assertion that Lener is a proponent of anything.



The objection made by Lerner is that a test at UV wavelengths is the real deal to test galaxies evolution. = ( This is the model he use )

This is not his objection.
Read what he asserts in chapter 3.1 page 8 in the 2005 paper: http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2
His unsupported assertion (note the lack of citations) is there is an upper limit on the UV surface brightness in galaxies and thus the UV band is better for the test. This actually sounds reasonable until you realize that he has a "population of N hot bright stars" where N is a constant.

What he ignores is that galaxies evolve. Thus even the UV surface brightness varies with time.

This is not the worst part of the presentation. The really dumb part is that he compares a scientific model of the universe (the LCDM model) with a toy model that has no relationship with reality (his ENE model).
The first break with reality is that he throws away Special Relativity with the Euclidean part of his Euclidean non-expanding universe.
Then there is the non-expanding part means that somehow his galaxies have been accelerated to values of z that just happen to mimic an expanding universe.
The non-expanding part is ridiculous given the existence and properties of the CMB.
What happens if we run his toy model backwards? All 100 billion galaxies in the observable universe end up packed into the Milky Way. We call that a supermassive black hole!
This also makes the Milky Way (or maybe the Earth) a privileged location in the universe.
A non-expanding universe has been around forever so we run against Olbers' paradox.
The galaxies in a non-expanding universe have always existed. and so there should be no neutral hydrogen in the universe (light ionizes it). But we observe that neutral H exists and that it increases as we look back in time (Lyman-alpha forest (http://en.wikipedia.org/wiki/Lyman-alpha_forest) that turns into the Gunn–Peterson trough (http://en.wikipedia.org/wiki/Gunn%E2%80%93Peterson_trough) at z > ~6). This is evidence that galaxies have not always existed.

ETA:
Don't you find it strange that there is no sign that this non-peer reviewed presentation at a conference in 2005 has been published in a scientific journal?
Don't you find it strange that there is no sign that Lener's next non-peer reviewed presentation at the next conference in 2008 has been published in a scientific journal?
If a conference presentation is not published then the implications are

The author has found flaws in the science and decided not to publish or
The author has no confidence in the science and decided not to publish or
The presentation was submitted to journals but rejected by the editors as obviously flawed or
The presentation was submitted to journals but the reviews pointed out enough flaws for the editors to reject it.

WayneFrancis
2012-May-15, 02:02 AM
...

Who has examined this paper? Originally published in 2005 I can find no citation. Nothing that denies the claim for example.

This kind of question/statement always makes me chuckle. Who honestly expects hard working people to publish papers to specifically disprove an idea that isn't even accepted? It is one thing to cite papers in support or cite papers and refute conclusions if your conclusion conflict with the current accepted models but to go out and write a paper to explicitly refute a fringe idea is practical most of the time.

The power of a paper is most easily gauged by the number of people that use that work in theirs. Kind of there is a "Like" in face book but no "Dislike". It isn't like slash dot ratings :)

WayneFrancis
2012-May-15, 02:15 AM
He is not claiming that cz/H_0 is concordance cosmology, it's an assumption that he is making for comparison and is specifically not the concordance model.

OK, just to be sure I understand correctly, his plot for LCDM is entirely wrong and he must be using the wrong mathematics. It's too bad that everybody is too busy to tell him that. Consider this, that such things can mislead the public, so maybe it is worth someone actually writing a paragraph to respond to it publicly. After all, the people on this forum are constantly correcting people on their misconceptions.

...


If he ever tried to get that paper into a normal journal he probably has. I'll also bet he's also ignored the reviewers.

Don J
2012-May-15, 04:02 AM
This is not the worst part of the presentation. The really dumb part is that he compares a scientific model of the universe (the LCDM model) with a toy model that has no relationship with reality (his ENE model).


Lets talk about some strange concept the current scientific model propose :

Dark Matter annihilations in Pop III stars

'Frozen' stars could shed light on dark matter
NewScientist article
http://www.newscientist.com/article/dn14197


The universe's first stars were the rock stars of the stellar world: they lived fast and died young, burning out in only a few hundred thousand years.

But new research suggests some of them might still be around as a result of interactions with dark matter, which halted their growth and curbed their blazing excess.

"These stars can be frozen for timescales longer than the age of the universe," said Gianfranco Bertone of the Paris Institute of Astrophysics in France.


Gianfranco Bertone paper on which is based the article.
http://arxiv.org/abs/0806.2681

Excerpt from the abstrac:
these stars exceeds the age of the Universe,
..."We determine the observational properties of these `frozen` objects and show that they can be searched for in the local Universe thanks to their anomalous mass-radius relation, which should allow unambiguous discrimination from normal stars."

parejkoj
2012-May-15, 04:15 AM
So you are taking issue with his representation of the theoretical LCDM magnitude/red-shift relationship? Your first plot shows how LCDM theory is different from what he is claiming in his Figure 1 where he states "obtained from the concordance cosmology with Omega_M=0.26 and Omega =0.76 (dashed line)". If that's the plot you want me to make, I don't know how, but I can try to find out.

No, I want you to make the plot that I described in the text:


...download the data from the Union2 team, plot z vs. mu, and then overplot z vs. mu for LCDM, cz/H_0, and whatever other cosmology you prefer.

Please tell me what's confusing about what I've written there? What part of that do you not understand, or find confusing?


You have no issue with his claim that mu=5log(cz/H0)-5 closely matches the SN data. Correct?

Let's look back at what I said earlier, as I thought I was being pretty explicit about this:


This is not "[an] agreement ... better than 0.3 mag over the whole range of redshift up to z =5..." In fact, here's how different they are across the redshift range:

16873




Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable. If you don't believe me, you can download the supernova data and try it yourself.

In fact, his non-expanding cosmology is ruled out quite nicely by the supernova data. Seriously: download the data from the Union2 team, plot z vs. mu, and then overplot z vs. mu for LCDM, cz/H_0, and whatever other cosmology you prefer. You've done a lot of accusing of astronomers of not doing their homework on these threads, but I haven't seen you do any actual calculations yourself.


I suppose I shouldn't have said "laughable," but rather "completely and utterly pants-on-fire (http://static.politifact.com.s3.amazonaws.com/rulings%2Ftom-pantsonfire.gif) false," which would be wildly obvious to you if you made said plot.

How can I make my point more clear? Seriously, I thought I was being crystal clear about the situation, but apparently I wasn't.


OK, I've went on a hunt for LCDM graphs and I think I have verified that his graph for the LCDM curve is not quite correct. If you look at the highest point that he plots (around log(z) = 0.25), mu should be about 45, not 44.5 as he shows.

You're going looking for plots instead of making your own. I don't know and don't care where you've gone "on a hunt for LCDM graphs", but you aren't going to learn what's going on here until you do the calculations. There's no point in talking about the rest of Lerner's plots until you work through this one.

Shaula
2012-May-15, 04:44 AM
Lets talk about some strange concept the current scientific model propose
How are speculative extensions that are valid within a model given a range of unproven assumptions even vaguely related to the topic?

The paper does state that it is highly dependent on the DM/baryon cross section for interaction. Which is an unknown quantity but constrained to be very low. It is also dependent on very high DM concentrations (which is related to the first assumption). Finally it is heavily dependent on DM-DM interactions (annihilation events). Which again we don't know anything about because we have not characterised DM that well.

Don J
2012-May-15, 05:01 AM
How are speculative extensions that are valid within a model given a range of unproven assumptions even vaguely related to the topic?

The paper does state that it is highly dependent on the DM/baryon cross section for interaction. Which is an unknown quantity but constrained to be very low. It is also dependent on very high DM concentrations (which is related to the first assumption). Finally it is heavily dependent on DM-DM interactions (annihilation events). Which again we don't know anything about because we have not characterised DM that well.

I want to verify if this is a peer reviewed paper accepted for publication in the mainstream scientific community ?

slang
2012-May-15, 05:10 AM
Excerpt from the abstrac:
these stars exceeds the age of the Universe,

What do you think that means, the part you quoted (badly)?

Don J
2012-May-15, 05:13 AM
What do you think that means, the part you quoted (badly)?

Can you tell me which part I have quoted (badly) ?

slang
2012-May-15, 05:17 AM
Can you tell me which part I have quoted (badly) ?

Sure. You left something essential out at the start of the sentence. Now please tell me what you thought it meant?

Don J
2012-May-15, 05:26 AM
Sure. You left something essential out at the start of the sentence. Now please tell me what you thought it meant?
Here the full quote preciding the (snippet)
We study the impact of the capture and annihilation of Weakly Interacting Massive Particles (WIMPs) on the evolution of Pop III stars. With a suitable modification of the Geneva stellar evolution code, we study the evolution of 20 and 200 M$_\odot$ stars in Dark Matter Haloes with densities between 10$^{8}$ and $10^{11}$ GeV/cm$^3$ during the core H-burning phase, and, for selected cases, until the end of the core He-burning phase. We find that for WIMP densities higher than 5.3 $10^{10}(\sigma^{SD}_p/10^{-38} {cm}^2)^{-1}$ GeV cm$^{-3}$ the core H-burning lifetime of $20 M_{\odot}$ and $200 M_{\odot}$stars exceeds the age of the Universe,
and the sentence following it "and stars are sustained only by WIMP annihilations."

slang
2012-May-15, 05:29 AM
Here the full quote preciding the (snippet)

I know. You already linked to it. I've read it. That's not what I asked, is it? What do you think that sentence means?

Don J
2012-May-15, 05:40 AM
I know. You already linked to it. I've read it. That's not what I asked, is it? What do you think that sentence means?
Excerpt from the abstrac:
http://arxiv.org/abs/0806.2681
[these] stars exceeds the age of the Universe,and [these] stars are sustained only by WIMP annihilations.


You mean what I think that sentence means in the context it is presented in rapport with the actual LCDM mainstream model ?

slang
2012-May-15, 05:51 AM
You mean what I think that sentence means in the context it is presented in rapport with the actual LCDM mainstream model ?

No, I'm interested in its implications vis-a-vis the existance of nano-gnomes... If you'd just answered my question I'd be able to respond to it. Alas, your usual dodging any question asked of you has almost made me late for work.

Now please stop dodging, and just answer the question. What do you think it means?

Jeff Root
2012-May-15, 05:51 AM
I was surprised when I read the abstract. That *was*
very badly quoted.

-- Jeff, in Minneapolis

Don J
2012-May-15, 05:55 AM
I was surprised when I read the abstract. That *was*
very badly quoted.

-- Jeff, in Minneapolis

As you see that is not my fault !But Slang put the blame on me .Ho My!

Don J
2012-May-15, 06:09 AM
and just answer the question. What do you think it means?

-[these] stars exceeds the age of the Universe, and [these] stars are sustained only by WIMP annihilations.-

That the WIMP annihilations thingy Dark Matter have the power to stop stars in their evolution ....if i read the Paper and the NewScientist article correctly.

http://www.newscientist.com/article/dn14197

http://arxiv.org/abs/0806.2681

antoniseb
2012-May-15, 11:45 AM
... ....if i read the Paper and the NewScientist article correctly. ...
New Scientist is cool, but they do tend to publish astonishingly fringe science on a regular basis. Don't cite single papers from there unless you have a lot more to back up your conclusion than one sentence and IIRC.

tusenfem
2012-May-15, 12:22 PM
As you see that is not my fault !But Slang put the blame on me .Ho My!

I guess your "copy/paste" did not work?
I fail to see why that was "not your fault."

The main stuff is in the beginning of the sentence, acually:We find that for WIMP densities higher than 5.3 1010(σSDp/10-38 cm2)-1 GeV cm-3 the core H-burning lifetime of 20 Mo and 200 Mo stars exceeds the age of the Universe, and stars are sustained only by WIMP annihilations.

So there is a condition to "these stars exceeding the age of the universe." And going to the conclusions, this is explained a bit better than in the abstract.

I also fail to see the reason bringing up this paper. It seems you want to justify whatever Lerner is claiming with his ENE model by quoting a paper that you think is strange too, and sidetracking this whole discussion that was going on.

Jeff Root
2012-May-15, 01:16 PM
Yeah, Don. Who did the bad quoting job if it wasn't you?

I suspect that you have no idea why we are saying you did
such a bad job of quoting. If that is the case, you need to
carefully re-read the full sentence, including the beginning
which you left off, and think about what it says. While
context is important, it isn't what makes the big difference
in this case. Just the beginning of the sentence.

However...

A couple of weeks ago I carefully read and re-read a post
by BigDon, and finally replied to it saying what I thought
he said in it. What I thought he said was very simple:
He was offering to make a map of where the people who
post on BAUT are located, by using a big catapult and
the nearby San Francisco Airport. It turned out that that
was not what he meant. What he meant was also very
simple: He was telling us his location so that someone
else could add it to a map of where the people who post
on BAUT are located, and that location was close enough
to the San Fransisco Airport that something hurled by a
big catapult from his home would be able to reach the
airport. Once I knew what he meant, it was obvious.
But until it was explained to me, I could only interpret
what he said incorrectly, and in a ridiculous way.

-- Jeff, in Minneapolis

TooMany
2012-May-15, 03:32 PM
You're going looking for plots instead of making your own. I don't know and don't care where you've gone "on a hunt for LCDM graphs", but you aren't going to learn what's going on here until you do the calculations. There's no point in talking about the rest of Lerner's plots until you work through this one.

Plot what? I don't know precisely how the theoretical distance modulus/redshift relation is computed in LCDM. I believe that it's currently adjusted (with a lambda) for a best match with the SN data. I've seen dozen's of plots of this data. (Something bothersome about the SN evidence for acceleration is the scatter and size of the error bars in those plots. It's really surprising that you can determine a deviation from no acceleration with confidence that is much smaller than both the scatter and error bars. Anyway this is beside the point and has nothing to do with the paper.)

If you have more criticism of the paper, I'm all ears.

slang
2012-May-15, 04:28 PM
That the WIMP annihilations thingy Dark Matter have the power to stop stars in their evolution ....

Well there you go. That wasn't so difficult, was it?


As you see that is not my fault !But Slang put the blame on me .Ho My!

Always, blame Canada! :) Seriously though, you did mangle that quote quite badly. As you quoted it, it suggests that those stars are older than the universe... Similar the old creationist claim argument. However with "the core H-burning lifetime of" left in, it becomes clear that these kinds of stars may still exist, as they can live longer than the universe exists. Since your quote has a different meaning than what is in the abstract, I tried to find out what you meant, and perhaps why you quoted it the way you did. Terrible, ain't I?

parejkoj, the union2.1 data is easy to find on your link, but I didn't quickly find a 'legend' explaining which field is what in the text file.

parejkoj
2012-May-15, 04:54 PM
parejkoj, the union2.1 data is easy to find on your link, but I didn't quickly find a 'legend' explaining which field is what in the text file.

Hey, someone's reading my posts. Yay!

Sadly, the page doesn't have the best layout (e.g. I wish they had high resolution PNGs in addition to the PDFs of the plots). Information on what's in the files is given in the "description" links just under each file. That should get you where you want. Oh, and it's a tab-delimited file, not space delimited (that tripped me up the first time I tried to use it).

For those trying to make the plot I described, I recommend starting a new thread about it, as this one is rather cluttered.

slang
2012-May-15, 05:27 PM
Hey, someone's reading my posts. Yay!

Wholly by accident, I assure you! :P Thanks.

Don J
2012-May-15, 06:39 PM
I guess your "copy/paste" did not work?
I fail to see why that was "not your fault."

The main stuff is in the beginning of the sentence, acually:We find that for WIMP densities higher than 5.3 1010(σSDp/10-38 cm2)-1 GeV cm-3 the core H-burning lifetime of 20 Mo and 200 Mo stars exceeds the age of the Universe, and stars are sustained only by WIMP annihilations.

So there is a condition to "these stars exceeding the age of the universe." And going to the conclusions, this is explained a bit better than in the abstract.

I have specifically quoted that sentence because i though it sounded like science fiction and it was probably bad quoted in the context of the LCDM model who claim that the Universe started about 13.5 billion years ago.I think that a better wording would be -that these kinds of stars who were formed 1 billion years after the Big Bang may still exist today-.

Now you will have to explain another thing who sounds like science -fiction.


Stellar resurrection

Other types of stars might also be transformed by dark matter. Present-day stars born in regions of high dark-matter density could also be affected, scientists say.

Dark matter might even have the power to resurrect dead stars. White dwarfs, the corpses of Sun-like stars, are extremely dense and could make excellent dark matter absorbers.

If a roving white dwarf were to wander into a region of abundant dark matter, it could be transformed into a dark matter burner, Moskalenko says: "They could shine like 30 Suns just because they are burning dark matter."




I also fail to see the reason bringing up this paper. It seems you want to justify whatever Lerner is claiming with his ENE model by quoting a paper that you think is strange too, and sidetracking this whole discussion that was going on.
It it just that i finded these claims so surreal than I wanted to verify it they were accepted by the mainstream.

I will return adressing some points about Lerner's paper.

parejkoj
2012-May-15, 06:47 PM
Plot what?

Please carefully read this post of mine (http://www.bautforum.com/showthread.php/132173-Creation-of-new-galaxies?p=2017729#post2017729) again, including the quoted sections, and answer the questions I asked. I thought I was being pretty clear, but it seems like you really aren't understanding me, and I'd love to know why.


I don't know precisely how the theoretical distance modulus/redshift relation is computed in LCDM.

Well, then, you could follow my advice and start a thread in Q&A to ask how to do so. I've given you some hints in this thread; there's a numeric integral involved.


I believe that it's currently adjusted (with a lambda) for a best match with the SN data.

Your belief in that matter is incorrect. One can make a direct prediction of the z vs. mu curve from the WMAP, or WMAP+BAO, or whatever, best-fit parameters, and see where the supernova data lie in regards to that prediction. One can then make the same prediction for the cosmology of their choice, and see how it compares. That's what I've been trying to get you to do. One could then compute a chi-squared or other statistic to see which cosmology makes the best such prediction.


(Something bothersome about the SN evidence for acceleration is the scatter and size of the error bars in those plots. It's really surprising that you can determine a deviation from no acceleration with confidence that is much smaller than both the scatter and error bars. Anyway this is beside the point and has nothing to do with the paper.)


And this is why we don't do chi-by-eye, and also why we actually do the calculations for the different cosmologies, instead of making guesses.

Don J
2012-May-15, 07:45 PM
This is not the worst part of the presentation. The really dumb part is that he compares a scientific model of the universe (the LCDM model) with a toy model that has no relationship with reality (his ENE model).
The first break with reality is that he throws away Special Relativity with the Euclidean part of his Euclidean non-expanding universe.
Then there is the non-expanding part means that somehow his galaxies have been accelerated to values of z that just happen to mimic an expanding universe.
The non-expanding part is ridiculous given the existence and properties of the CMB.

Read this thread who propose an alternative explanation about the accelarating (expanding )universe ...
http://www.bautforum.com/showthread.php/129672-Accelerating-Universe-possible-explanation



What happens if we run his toy model backwards? All 100 billion galaxies in the observable universe end up packed into the Milky Way. We call that a supermassive black hole!

He dont have to run the ENE model backward.


The galaxies in a non-expanding universe have always existed. and so there should be no neutral hydrogen in the universe (light ionizes it). But we observe that neutral H exists and that it increases as we look back in time (Lyman-alpha forest (http://en.wikipedia.org/wiki/Lyman-alpha_forest) that turns into the Gunn–Peterson trough (http://en.wikipedia.org/wiki/Gunn%E2%80%93Peterson_trough) at z > ~6). This is evidence that galaxies have not always existed.

1-No, the Galaxies have not always existed and they evolue in Perratt and Lerner ENE model.

2-Can you cite me something where they claim that neutral H do not exist ?
However as you can see in the Wiki article the interstellar space medium is mostly ionized and i think (but i may be wrong) that the intergalactic space medium is also mostly ionized.
http://en.wikipedia.org/wiki/Interstellar_medium

3-( Layman Alpha forest and Gunn-Petterson )That is evidence that there is a lot of stuff betwen our point of observation and these Galaxies.

TooMany
2012-May-15, 09:39 PM
No I am not. Read what I wrote - no assertion that Lener is a proponent of anything.

Read what he asserts in chapter 3.1 page 8 in the 2005 paper: http://search.arxiv.org:8081/details.jsp?qid=1336800907476mix_nCnN_1197605709&r=pdf/astro-ph/0509611v2
His unsupported assertion (note the lack of citations) is there is an upper limit on the UV surface brightness in galaxies and thus the UV band is better for the test. This actually sounds reasonable until you realize that he has a "population of N hot bright stars" where N is a constant.

What he ignores is that galaxies evolve. Thus even the UV surface brightness varies with time.

This is not the worst part of the presentation. The really dumb part is that he compares a scientific model of the universe (the LCDM model) with a toy model that has no relationship with reality (his ENE model).


It seems to me that in your eagerness to condemn his paper you choose to ignore that he has stated these assumptions as a premise for a comparison of data. You may think the premises are nuts, but that's not really quite the point. Although he does not make it explicitly clear enough for you in the paper, ENE is an assumption of a static universe, not one evolving from a beginning. Therefore part of the assumption is that galaxies at high z are no different from those now. You can condemn his premises all you want, but all you are doing is ignoring the content and conclusion of the paper which is that the premises fit this particular bit of data (surface brightness measures). In order for LCDM to match the observations, it must assume that evolution precisely accounts for it. Since we don't know all that much about evolution it's a completely open question as to whether LCDM gets the surface brightness test right. It's going to take a lot more data to make that test solid (maybe the JWT will do it by shedding more light on evolution). In the meantime all LCDM has to do is say "it's evolution". In his (however crazy model), the measured surface brightness matches the model, with the data we already have. This does not prove that his assumptions themselves are correct, it is just an interesting observation.

If you disagree with that, then tells us why?

Reality Check
2012-May-15, 09:45 PM
Read this thread who propose an alternative explanation about the accelarating (expanding )universe ...

An ATM thread that does not even mention the CMB! You need to actually read what you link to.
What remains correct is that Lerner uses a toy model that has no relationship with reality (his ENE model):
* he throws away Special Relativity with the Euclidean part of his Euclidean non-expanding universe.
* somehow his galaxies have been accelerated to values of z that just happen to mimic an expanding universe.
* the non-expanding part is ridiculous given the existence and properties of the CMB.
If you can find a Euclidean non-expanding model that predicts the measured properties of the CMB then I would be intersted in a link to the published paper.

Lerner ignores the evolution of galaxies which changes their surface brightness. That immediately invalidates his presentation.


He dont have to run the ENE model backward.

The fact that he did not realize that runing his ENE model backwards makes it invalid is the point.



1-No, the Galaxies have not always existed and they evolue in Perratt and Lerner ENE model.

Galaxies always exist in a non-expanding universe because there is no point at which they do not exist. Lerner's ENE model does not include galaxies popping into existence.

Galaxies do not evolve in the Lerner ENE model otherwise you would quote the part of the model that decribes the galaxy evolution.
What you ignored in my post is Lerners assertion that galaxies do not evolve!

His unsupported assertion (note the lack of citations) is there is an upper limit on the UV surface brightness in galaxies and thus the UV band is better for the test. This actually sounds reasonable until you realize that he has a "population of N hot bright stars" where N is a constant.

Galaxies actually have a population of N(t) hot bright stars where N(t) is a function of time.

The Peratt model is so bad that even undergraduate students can understand that it is wrong, e.g. it has spiral galaxies with no matter in between their arms (the density of matter is 10-20% less, not zero) and Peratt himself debunks it by showing that the gravitational component in his model is 10,000,000 times larger than the EM component (see Anthony Peratt's Plasma Model of Galaxy Formation (http://forums.randi.org/showthread.php?t=144610) in the JREF forum).



Can you cite me something where they claim that neutral H do not exist ?

Who is "they"?

The current intergalactic space medium is mostly ionized. The cause of that ionization is the radiation from galaxies. The Layman Alpha forest and Gunn-Petterson trough are evidence that galaxies came into existence and started ionizing the neutral hydrogen.

TooMany
2012-May-15, 09:48 PM
And this is why we don't do chi-by-eye, and also why we actually do the calculations for the different cosmologies, instead of making guesses.

Great, but when I was taking physics, the professor would laugh if I drew conclusions so fine from data so coarse. It seems to be the norm in astronomy these days to use complex statistical arguments to tease out very modest underlying effects such as BAO and then announce the ability to determine distances using the effect to a few percent. This stuff (SN evidence for acceleration) would be a lot more persuasive if at least the scatter and the error bars were smaller than the claimed effect. Then there is the whole issue of systematic errors as well.

I realize that people are trying to squeeze the most they can out of the data they have, but this is nothing like the degree of accuracy we normally expect in science for something to be a fact. What would you say the sigma significance is for an accelerating universe in this data?

Maybe that should be a separate conversation. I'm more interested in what you have to say about this Lerner paper. You were right about the first mistake, but as I pointed out it's not directly pertinent to the rest of the paper. You can't rest on your laurels just yet. You have condemned it so far on Lerner's error concerning the difference between the linear and LCDM prediction. I think you are right, he has misstated the size of the difference.

You have also said that he is not an astronomer, meaning I guess that only bona fide astronomers are permitted to examine the data. You have argued that he is "always wrong". How is he wrong this time? Please don't repeat that his assumptions are wrong. That is not the issue.

Reality Check
2012-May-15, 10:08 PM
Although he does not make it explicitly clear enough for you in the paper, ENE is an assumption of a static universe, not one evolving from a beginning.

My point is that comparing the LCDM model which matches (mostly) the real universe with a model that largely ignores the real universe is dumb.

P.S. It is not a paper. At best it is a conference presentation. It may even just be a conference poster where an author puts ongoing work on a poster for other people to read.


Therefore part of the assumption is that galaxies at high z are no different from those now.

Galaxies that are at high z are younger than galaxies at lower z. They are different from those now because their stellar populations are different.

The LCDM model does not say "it's evolution". Physics says that galaxies evolve and change their surface brightness. Ignoring this invalidates any Tolman SB test. Lerner ignores this even for his match for the the LCDM model!

The best you can say about his conference presentation is that he has a toy model that can match a badly performed Tolman SB test. He then compares this to an equally badly performed Tolman SB test of the LCDM model. His toy model matches better than the LCDM (according to him but see the other posts here about problems with his analysis).
This does not show anything about the validity of either model.

Don J
2012-May-16, 01:30 AM
Galaxies that are at high z are younger than galaxies at lower z. They are different from those now because their stellar populations are different.

their stellar populations are different.

I take it as you are saying that these young galaxies at high z are more brighter than the actual galaxies because the stars in those young high z Galaxies were different than those in the actual galaxies. Right?

Eta
(Lets compare a young spiral galaxie of the same surface brightness at high z =6 and our Milky Way Galaxy))

What are the population of stars in those young spiral galaxies at high z made of -which allow them to be more brighter in the past- ... compared to a similar sized spiral Galaxie like our Milky Way ?

Reality Check
2012-May-16, 02:29 AM
their stellar populations are different.
I take it as you are saying that these young galaxies at high z are more brighter than the actual galaxies because the stars in those young high z Galaxies were different than those in the actual galaxies. Right?

I am saying that stars evolve, so galaxies evolve and so surface brightness changes.
I do not know the difference that the models show but the fact is that astronomers using the Tolman SB test account for this galaxy evolution.

ETA: The main sequence burn down corrects the magnitude (and so SB) by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

Don J
2012-May-16, 03:14 AM
I am saying that stars evolve, so galaxies evolve and so surface brightness changes.
I do not know the difference that the models show but the fact is that astronomers using the Tolman SB test account for this galaxy evolution.

ETA: The main sequence burn down corrects the magnitude (and so SB) by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

By star "evolve" you mean the sequence of
Life and death of stars ... Right?
http://map.gsfc.nasa.gov/universe/rel_stars.html

So young Galaxies at high Z are brighter because the ratio of new born stars was higher. Right?

Don J
2012-May-16, 05:18 AM
Development
The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies revisited in 2006.


http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0605599&qid=1337144768109mix_nCnN_-1528929564&qs=The+Tolman+Surface+Brightness+Test+for+the+Real ity+of+the+Expansion.+IV.+A+Measurement+of+the+Tol man+Signal+and+the+Luminosity+Evolution+of+Early+T ype+Galaxies%2C

Here the 2001 Tolman Surface Brightness Test for reference

http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0106566&qid=1337144768109mix_nCnN_-1528929564&qs=The+Tolman+Surface+Brightness+Test+for+the+Real ity+of+the+Expansion.+IV.+A+Measurement+of+the+Tol man+Signal+and+the+Luminosity+Evolution+of+Early+T ype+Galaxies%2C

tusenfem
2012-May-16, 08:14 AM
http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0605599&qid=1337144768109mix_nCnN_-1528929564&qs=The+Tolman+Surface+Brightness+Test+for+the+Real ity+of+the+Expansion.+IV.+A+Measurement+of+the+Tol man+Signal+and+the+Luminosity+Evolution+of+Early+T ype+Galaxies%2C


OMG not Brynjolfsson!
That is totally crank, ATM, and does not belong here.
He does not even have one peer-reviewed paper in the literature, the only thing he seems to have is some meeting abstracts and some arxiv documents. His plasma redshift ideas are totally unteneble and if I remember correctly fully discussed on JREF by Nereid and I am sure Reality Check has the links somewhere.

antoniseb
2012-May-16, 10:54 AM
... His plasma redshift ideas are totally unteneble ....

... And are an example of a tired light hypothesis which as we noted a couple days ago is falsified by the width of light-curves (duration above half-maximum) as a function of redshift for type 1a supernovae, among other things.

Cougar
2012-May-16, 12:29 PM
If you have more criticism of the paper, I'm all ears.

What, you haven't heard enough??? Do you just skip over parts you don't want to hear? such as:


Certainly, his claim that a z vs. mu plot for supernova would match a line with mu~cz/H_0 is laughable.... I suppose I shouldn't have said "laughable," but rather "completely and utterly pants-on-fire false," which would be wildly obvious to you if you made said plot.

Why would you need more criticism than that?

Don J
2012-May-16, 07:25 PM
I am saying that stars evolve, so galaxies evolve and so surface brightness changes.
I do not know the difference that the models show but the fact is that astronomers using the Tolman SB test account for this galaxy evolution.

ETA: The main sequence burn down corrects the magnitude (and so SB) by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

Is it true that the contemporary big-bang cosmology predicted that the surface brightness is inversely proportional to the fourth power of (1+z)?

If so then "Houston" there is a problem for the Big Bang ...
That is not what Lori M. Lubin and Allan Sandage, find when they compiled the datas...
In 2001 Lori M. Lubin and Allan Sandage, using big-bang cosmology for interpreting the data, found the surface brightness of galaxies to be inversely proportional to about the third power of (1+z),

That explain why they tweaked the original equation to account for the discrepency...


ETA: The main sequence burn down corrects the magnitude (and so SB) by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

antoniseb
2012-May-16, 07:31 PM
Is it true that the contemporary big-bang cosmology predicted that the surface brightness is inversely proportional to the fourth power of (1+z)?...

Surface brightness? No. For a point source yes, but for surface brightness, it is just inverse square.

Don J
2012-May-16, 07:41 PM
Surface brightness? No. For a point source yes, but for surface brightness, it is just inverse square.
Lets see the quote in context and tell me if there is something wrong in the whole sentence :


"In 2001 Lori M. Lubin and Allan Sandage, using big-bang cosmology for interpreting the data, found the surface brightness of galaxies to be inversely proportional to about the third power of (1+z), while the contemporary big-bang cosmology predicts that the surface brightness is inversely proportional to the fourth power of (1+z). In contrast, these surface brightness observations are in agreement with the predictions of the plasma-redshift cosmology. Lubin and Sandage (2001) and Barden et al. (2005), who surmised the big-bang expansion, interpreted the observations to indicate that the diameters of galaxies are inversely proportional to (1+z). "

Here Reality Check talk (see post 110) about the tweak they have made to account for the discrepency betwen the original prediction and the datas collected.


The main sequence burn down corrects the magnitude (and so SB) by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

antoniseb
2012-May-16, 08:15 PM
There are a lot of factors, and they aren't all linear or monotonic... such as the sensitivity of the sensor to the wavelength of the photons received. There are some peak brightnesses in visible and uv, for example. There are also more predictable factors such as the spreading out of photons during the expansion (or time dilation if you think their moving). But magnitude of the object is not the same as brightness of a square arcsecond of an object. You seem to be confusing the two.

TooMany
2012-May-16, 08:45 PM
My point is that comparing the LCDM model which matches (mostly) the real universe with a model that largely ignores the real universe is dumb.

P.S. It is not a paper. At best it is a conference presentation. It may even just be a conference poster where an author puts ongoing work on a poster for other people to read.


Galaxies that are at high z are younger than galaxies at lower z. They are different from those now because their stellar populations are different.

The LCDM model does not say "it's evolution". Physics says that galaxies evolve and change their surface brightness. Ignoring this invalidates any Tolman SB test. Lerner ignores this even for his match for the the LCDM model!

The best you can say about his conference presentation is that he has a toy model that can match a badly performed Tolman SB test. He then compares this to an equally badly performed Tolman SB test of the LCDM model. His toy model matches better than the LCDM (according to him but see the other posts here about problems with his analysis).
This does not show anything about the validity of either model.

How many times does it have to be stated. He chooses to make certain assumptions (like no evolution) and he finds that surface brightness data match. You can disagree with his premises, but I'm really more interested in whether you disagree that the conclusion (based on the premises) is correct regardless of how stupid the premises are. And yes, I pretty much agree with your statement that I put in bold above.

Reality Check
2012-May-16, 09:00 PM
Lets talk about some strange concept the current scientific model propose :

Is the abandonment of the Lerner conference presentation topic imply that you agree that the presentation is fatally flawed since he does not include galaxy evolution and uses an unphysical toy model?

Dark Matter annihilations in Pop III stars (http://arxiv.org/abs/0806.2681) is a nice little bit of theory that calculates an upper limit on the density of WIMPs (otherwise stars would be older than the age of the universe).

Reality Check
2012-May-16, 09:05 PM
He chooses to make certain assumptions (like no evolution) and he finds that surface brightness data match. You can disagree with his premises, but I'm really more interested in whether you disagree that the conclusion (based on the premises) is correct regardless of how stupid the premises are. And yes, I pretty much agree with your statement that I put in bold above.
His choices make his Tolman SB tests invalid and so this conference presentation is invalid. The conclusion (based on the premises) is wrong regardless of how stupid the premises are.

Reality Check
2012-May-16, 09:19 PM
Is it true that the contemporary big-bang cosmology predicted that the surface brightness is inversely proportional to the fourth power of (1+z)?
...
That explain why they tweaked the original equation to account for the discrepency...
Galaxy evolution explains why any competent astronomer would "tweak" the contemporary big-bang cosmology (which does not include stellar and galaxy evolution) prediction.

In 2001 Lori M. Lubin and Allan Sandage, using big-bang cosmology and galaxy evolution shows that the surface brightness is inversely proportional to the about the third power of (1+z) .
Read the abstract and the paper:
The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies (http://arxiv.org/abs/astro-ph/0106566)

We review a sample of the early literature in which the reality of the expansion is discussed, explain Hubble's reticence to accept the expansion as real, and contrast the Tolman surface brightness test with three other modern tests. We search for the Tolman surface brightness depression with redshift using the Hubble Space Telescope (HST) data from Paper III for 34 early-type galaxies from the three clusters Cl 1324+3011 (z=0.76), Cl 1604+4304 (z=0.90), and Cl 1604+4321 (z=0.92). Depressions of the surface brightness relative to the zero-redshift fiducial lines in the mean surface brightness, log linear radius diagrams of Paper I are found for all three clusters. Expressed as the exponent, n, in 2.5 log (1 + z)^n mag, the value of n for all three clusters is n = 2.59 +/- 0.17 in the R band and 3.37 +/- 0.13 in the I band for a q_o = 1/2 model. The sensitivity of the result to the assumed value of q_o is shown to be less than 23% between q_o = 0 and +1. For a true Tolman signal with n = 4, the luminosity evolution in the look-back time, expressed as the exponent in 2.5 log (1+z)^(4-n) mag, must then be between 1.72 to 1.19 in the R band and 0.94 to 0.45 in the I band. We show that this is precisely the range expected from the evolutionary models of Bruzual & Charlot. We conclude that the Tolman surface brightness test is consistent with the reality of the expansion. We have also used the high-redshift HST data to test the ``tired light'' speculation for a non-expansion model for the redshift. The HST data rule out the ``tired light'' model at a significance level of better than 10 sigma.

Reality Check
2012-May-16, 09:22 PM
So young Galaxies at high Z are brighter because the ratio of new born stars was higher. Right?
So young galaxies have a different surface brightness than current galaxies. If we just include the main sequence burn down then the magnitude (and so SB) changes by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.

Reality Check
2012-May-16, 09:40 PM
OMG not Brynjolfsson!
That is totally crank, ATM, and does not belong here.
He does not even have one peer-reviewed paper in the literature, the only thing he seems to have is some meeting abstracts and some arxiv documents. His plasma redshift ideas are totally unteneble and if I remember correctly fully discussed on JREF by Nereid and I am sure Reality Check has the links somewhere.
Plasma Redshift Cosmology Fails (http://forums.randi.org/showthread.php?postid=7393901#post7393901) by Tim Thompson
The math errors in the pre-print (http://forums.randi.org/showthread.php?postid=7393481#post7393481) by ben m

This is also a "tired light" cosmology so Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm) web page is applicable.

TooMany
2012-May-17, 12:20 AM
His choices make his Tolman SB tests invalid and so this conference presentation is invalid. The conclusion (based on the premises) is wrong regardless of how stupid the premises are.

That is most certainly a fallacy. His conclusion is completely contingent on the assumptions and his conclusion is that surface brightness data match his assumptions. That statement can be correct without the assumptions actually being correct. Your position is illogical.

Reality Check
2012-May-17, 12:46 AM
That is most certainly a fallacy. His conclusion is completely contingent on the assumptions and his conclusion is that surface brightness data match his assumptions. That statement can be correct without the assumptions actually being correct. Your position is illogical.
The logic is that Lerner states he is attempting the Tolman SB test. This test requires that the SB be calculated. If you ignore galaxy evolution then you will calculate the wrong SB. Thus Lerner's tests are invalid.

ETA: Noticed more stuff that makes this conference presentation bad - his references. They include his previous presentation and "Scarpa, R, Falamo R. and Lerner, E., 2009, in preparation" that I cannot find (it is not on Renato Falomo's publications page (http://web.oapd.inaf.it/falomo/publications.html)).

Swift
2012-May-17, 01:25 AM
That is most certainly a fallacy. His conclusion is completely contingent on the assumptions and his conclusion is that surface brightness data match his assumptions. That statement can be correct without the assumptions actually being correct. Your position is illogical.
No, that is it and you are done.

You are more than advocating ATM outside of ATM, you are advocating nonsense. This has been beaten to death.

TooMany, you get an infraction. I would normally close this thread, but others are talking about things, and I won't punish them. You WILL NOT post any longer in this thread. If you do, you will be infracted. If you have ANYTHING further to say about this or related topics, you will start your own thread, and I suggest you start it in ATM.

Don J
2012-May-17, 04:23 AM
So young Galaxies at high Z are brighter because the ratio of new born stars was higher. Right?

So young galaxies have a different surface brightness than current galaxies. If we just include the main sequence burn down then the magnitude (and so SB) changes by 2.5 log (1 + z) or about 2.1 for a z = 6 galaxy.
Can you provide comparative data made from direct observation than a new born star lets say a Main Sequence Star like our Sun is more luminous because it is a new born star versus the actual luminosity of the Sun ?
I always though than the luminosity of a star was defined like this (see quote below): ...., .. not by their age =new born star more luminous.???
http://map.gsfc.nasa.gov/universe/rel_stars.html


-For a given chemical composition and stellar age, a stars' luminosity, the total energy radiated by the star per unit time, depends only on its mass. Stars that are ten times more massive than the Sun are over a thousand times more luminous than the Sun. -

Jeff Root
2012-May-17, 05:37 AM
That is most certainly a fallacy. His conclusion is
completely contingent on the assumptions and his
conclusion is that surface brightness data match his
assumptions. That statement can be correct without
the assumptions actually being correct. Your position
is illogical.

No, that is it and you are done.

You are more than advocating ATM outside of ATM,
you are advocating nonsense. This has been beaten
to death.

TooMany, you get an infraction. I would normally
close this thread, but others are talking about things,
and I won't punish them. You WILL NOT post any longer
in this thread. If you do, you will be infracted. If you
have ANYTHING further to say about this or related topics,
you will start your own thread, and I suggest you start
it in ATM.
What 'TooMany' said was completely correct, though.

The changes to the data that 'Reality Check' thinks Lerner
should have made were not appropriate for the test Lerner
was conducting. They would ruin it. In that regard,
Reality Check's criticism of Lerner is wrong.

-- Jeff, in Minneapolis

tusenfem
2012-May-17, 06:23 AM
Plasma Redshift Cosmology Fails (http://forums.randi.org/showthread.php?postid=7393901#post7393901) by Tim Thompson
The math errors in the pre-print (http://forums.randi.org/showthread.php?postid=7393481#post7393481) by ben m

This is also a "tired light" cosmology so Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm) web page is applicable.

I knew I could count on you :)

Swift
2012-May-17, 01:32 PM
What 'TooMany' said was completely correct, though.

The changes to the data that 'Reality Check' thinks Lerner
should have made were not appropriate for the test Lerner
was conducting. They would ruin it. In that regard,
Reality Check's criticism of Lerner is wrong.

-- Jeff, in Minneapolis
Don't argue moderation in thread or you will be infracted

parejkoj
2012-May-17, 03:40 PM
What 'TooMany' said was completely correct, though.

The changes to the data that 'Reality Check' thinks Lerner
should have made were not appropriate for the test Lerner
was conducting. They would ruin it. In that regard,
Reality Check's criticism of Lerner is wrong.


No, Reality Check is completely correct. Galaxies are observed to be very different at high redshift. Their colors are different, their spectra are different, their luminosities are different, their shapes are different. We know that galaxy stellar populations change with redshift: we can observe it in the spectra. Since galaxies are made of stars, we also know something about how they will evolve with time, as the stellar populations change (passive aging, new star formation, blue stragglers, etc.). Ignoring this fact, particularly when assuming that redshift and distance (and thus time) are correlated--as Lerner does--invalidates any comparison one makes between high-redshift galaxies and local galaxies.

It's particularly bad when someone makes a claim that Lambda-CDM cosmology makes some prediction about how galaxies should look at different redshifts, without incorporating the known behavior of galaxies.

Jeff Root
2012-May-17, 04:23 PM
What 'TooMany' said was completely correct, though.

The changes to the data that 'Reality Check' thinks Lerner
should have made were not appropriate for the test Lerner
was conducting. They would ruin it. In that regard,
Reality Check's criticism of Lerner is wrong.
No, Reality Check is completely correct. Galaxies are
observed to be very different at high redshift.
Their colors are different, their spectra are different,
their luminosities are different, their shapes are different.
We know that galaxy stellar populations change with
redshift: we can observe it in the spectra. Since galaxies
are made of stars, we also know something about how
they will evolve with time, as the stellar populations
change (passive aging, new star formation, blue stragglers,
etc.). Ignoring this fact, particularly when assuming that
redshift and distance (and thus time) are correlated--as
Lerner does--invalidates any comparison one makes
between high-redshift galaxies and local galaxies.
No it does not. Lerner compared what his theory
predicted to what is seen. You want him to compare
what his theory predicted to what your theory says is
actually there.

What 'TooMany' said was completely correct. That
particular objection of 'Reality Check' and yours is wrong.

-- Jeff, in Minneapolis

Cougar
2012-May-17, 05:44 PM
Lerner compared what his theory
predicted to what is seen.

Oh, come on. Lerner's conclusion is wrong. His premises are wrong. How much more wrong do you want? Would you fight for someone with a "theory" that the Sun revolves around the Earth because that is "what is seen" from our vantage here on the surface? There are plenty of findings about which one might have a valid and worthwhile argument. This isn't one of them.

Jeff Root
2012-May-17, 06:02 PM
I'm not suggesting that Lerner's premises aren't wrong
or that his conclusion isn't wrong. I'm saying that the
criticism of his method in this thread is wrong, and that
what 'TooMany' said in post #126 was completely correct.

-- Jeff, in Minneapolis

Don J
2012-May-17, 06:37 PM
... And are an example of a tired light hypothesis which as we noted a couple days ago is falsified by the width of light-curves (duration above half-maximum) as a function of redshift for type 1a supernovae, among other things.
This was put in dispute by the same author which even seem to find a correlation whith the plasma redshift mechanism.

http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0602500&qid=13372274126429a_nCnN_-1528929471&qs=eric+lerner+supernova+

parejkoj
2012-May-17, 06:47 PM
No it does not. Lerner compared what his theory
predicted to what is seen. You want him to compare
what his theory predicted to what your theory says is
actually there.

No, I'm not talking about theory, I'm talking about observations. I gave a list of things that we've directly observed about galaxies at different redshifts that need to be taken into account when comparing across redshifts. They have nothing to do with theory. "What is seen" in this case includes the fact that you can't directly compare galaxies at z=0 with galaxies at z=1.

antoniseb
2012-May-17, 06:53 PM
This was put in dispute by the same author which even seem to find a correlation whith the plasma redshift mechanism. ...
Ari Brynjolfsson isn't really a credible reference here. If you'd like to start a thread in ATM arguing in favor of the position in the paper you cited, please do so. This reference really doesn't belong in the mainstream part of this forum.

Don J
2012-May-17, 07:03 PM
Ari Brynjolfsson isn't really a credible reference here. If you'd like to start a thread in ATM arguing in favor of the position in the paper you cited, please do so. This reference really doesn't belong in the mainstream part of this forum.
So I will let that aside.Do you have any reference to a rebuttal paper published or not about the intrinsic redshift of galaxies that he talks about I remember something similar was proposed by Halton Arp but cannot find a polite and enlighting rebuttal discussion about that.
For example:
That is the kind of sterile discussion I try to avoid


Plasma Redshift Cosmology Fails (http://forums.randi.org/showthread.php?postid=7393901#post7393901) by Tim Thompson
The math errors in the pre-print (http://forums.randi.org/showthread.php?postid=7393481#post7393481) by ben m



This is also a "tired light" cosmology so Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm) web page is applicable.
Ned Wright talk about the tired light hypothesis ....that is not the same think that the intrinsic redshift of galaxies proposed by the plasma redshift mechanism.

antoniseb
2012-May-17, 07:24 PM
... .that is not the same think that the intrinsic redshift of galaxies proposed by the plasma redshift mechanism.

Wow, we had a lot of ATM discussion about intrinsic redshift about 10 years ago here, but it hasn't really come up since.
The basic idea behind it wasn't so much the Plasma cosmology, but rather Halton Arp trying to make his case that quasars might not be as far away as we think, but rather they are spewed from the cores of active galactic nuclei, and are proto galaxies that look really small and have a high intrinsic redshift until the blossom into large full galaxies. (I'm paraphrasing). As far as I know, he gave no physics interpretation for how this could all happen, but rather left it to unknown science. In Arp's defense, let me say that he came to this conclusion when quasars were a very new discovery, and our instrumentation was much less capable... and I suspect he stuck to the position because it was interesting to him to see how long he could hold out against the other side.


I don't remember any specific summary papers where someone bothered to enumerate all of the observations that seem to conflict with Arp's idea... Once again, if you'd like to try to defend that idea in ATM, go ahead. I suspect you'll get the references you're looking for pretty promptly. To me, one of the biggest issues was that galaxies each have very close to the same redshift over many kiloparsecs, but most physical arguments for intrinsic redshift should be isolated to the central part, and have a lot of variation over the large expanse of a whole galaxy (again paraphrasing and summarizing without citation).

Don J
2012-May-17, 07:37 PM
Wow, we had a lot of ATM discussion about intrinsic redshift about 10 years ago here, but it hasn't really come up since.
The basic idea behind it wasn't so much the Plasma cosmology, but rather Halton Arp trying to make his case that quasars might not be as far away as we think, but rather they are spewed from the cores of active galactic nuclei, and are proto galaxies that look really small and have a high intrinsic redshift until the blossom into large full galaxies.
Thanks ,that is right Halton Arp quasars hypothesis have nothing to do with the plasma red-shift mechanism that the author propose.



I don't remember any specific summary papers where someone bothered to enumerate all of the observations that seem to conflict with Arp's idea

No, that is about Ari Brynjolfsson proposal of -intrinsic redshift of galaxies- based on the -plasma red-shift mechanism- . That i am looking for a rebuttal paper published or not.

Eta
I see that you have discussed about that in 2005.

http://www.bautforum.com/showthread.php/24161-Plasma-Red-shift

On post 3 you wrote:



Here&#39;s another arXiv paper by Ari Brynjolfsson.
http://www.arxiv.org/PS_cache/astro-ph/pdf/0408/0408312.pdf
In this one he is looking at the red shift of photons coming from the sun and going through the solar corona.

Weightlessness of photons: A quantum effect

He provides a quantum modification to the General Theory of Relativity and the equivalence principle.

I am not a believer in the plasma red-shift, but this guy definitely does his homework.


Interesting time we are living in, isn't it?

antoniseb
2012-May-17, 09:37 PM
... Interesting time we are living in, isn't it?

I believe these times are interesting, but don't see how this illustrates that, or what this has to do with your new tangent about Intrinsic Redshift of galaxies. My earlier hand-waving argument that trying to get a uniform plasma cosmology only redshift for an entire galaxy spanning 30 kpc being just unworkable still applies... and was a major reason that proponents seven years ago gave up the argument.

Reality Check
2012-May-17, 10:31 PM
Can you provide comparative data made from direct observation than a new born star lets say a Main Sequence Star like our Sun is more luminous because it is a new born star versus the actual luminosity of the Sun ?
The change in SB of a galaxy as it ages is caused by the change in the stellar population and other factors. This is something that you can look up yourself.

However a quick Google gives this lecture: STELLAR POPULATIONS AND THE HISTORY OF THE UNIVERSE (http://www.astro.virginia.edu/class/oconnell/astr130/Spops-HistUniv.html)

Reality Check
2012-May-17, 10:48 PM
Ned Wright talk about the tired light hypothesis ....that is not the same think that the intrinsic redshift of galaxies proposed by the plasma redshift mechanism.
Ari Brynjolfsson's plasma redshift is about the measured redshift of galaxies that give rise to Hubble's law and is explained by an expanding universe in standard cosmology. He tries to replace it by scattering from a hot plasma. So the light is "tired" by scattering. This has the same major problem as the tired light idea - see Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm):

There is no known interaction that can degrade a photon's energy without also changing its momentum, which leads to a blurring of distant objects which is not observed. The Compton shift in particular does not work.

Brynjolfsson's plasma redshift is nothing to do with any intrinsic redshift of galaxies.

Cougar
2012-May-18, 12:43 AM
Brynjolfsson's plasma redshift is nothing to do with any intrinsic redshift of galaxies.

Right, and these are both fringe ideas that have long been debunked. What is your interest in these things, Don J? Perhaps you're writing a book on kook science?

Don J
2012-May-18, 01:49 AM
Ari Brynjolfsson's plasma redshift is about the measured redshift of galaxies that give rise to Hubble's law and is explained by an expanding universe in standard cosmology. He tries to replace it by scattering from a hot plasma. So the light is "tired" by scattering. This has the same major problem as the tired light idea - see Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm):


Brynjolfsson's plasma redshift is nothing to do with any intrinsic redshift of galaxies.
Maybe you are not talking about the same Brynjolfsson's
quote from the abstrac


It predicts intrinsic redshifts of galaxies consistent with what is observed.

Here the abstract where the quote is located
http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0602500&qid=13372274126429a_nCnN_-1528929471&qs=eric+lerner+supernova+

Don J
2012-May-18, 01:50 AM
Right, and these are both fringe ideas that have long been debunked. What is your interest in these things, Don J? Perhaps you're writing a book on kook science?
Not really !

Don J
2012-May-18, 02:04 AM
I believe these times are interesting, but don't see how this illustrates that, or what this has to do with your new tangent about Intrinsic Redshift of galaxies. My earlier hand-waving argument that trying to get a uniform plasma cosmology only redshift for an entire galaxy spanning 30 kpc being just unworkable still applies... and was a major reason that proponents seven years ago gave up the argument.
Thanks for pointing your objection. I see that you mention in (post 17 old thread) something about SNAP satellite., why do you think at this time it was needed to settle the issue about Brynjolfsson plasma redshifht model ?


----"My biggest obstacles to his work have to do with
- the unprovalble physical process of the plasma red-shift [similar to CREIL]
- the dubious claims of the Type II Malmquist bias on time dilation of Type Ia Supernova light curves [I can hardly wait for SNAP to be launched and start producing results]."----
- his claim that plasma red-shift also causes the CMB [his math is pretty sparse there]

antoniseb
2012-May-18, 02:27 AM
Thanks for pointing your objection. I see that you mention in (post 17 old thread) something about SNAP satellite., why do you think at this time it was needed to settle the issue about Brynjolfsson plasma redshifht model ?
I do not recall precisely what I was thinking then (Post-edit: but it had to do with getting more statistics and data), but many other programs including OGLE and the supernova factory have given us what SNAP promised and more.

Reality Check
2012-May-18, 03:05 AM
Here the abstract where the quote is located
http://search.arxiv.org:8081/paper.jsp?r=astro-ph/0602500&qid=13372274126429a_nCnN_-1528929471&qs=eric+lerner+supernova+
That is only one of the many things that Brynjolfsson gets wrong!
His 'intrinsic' redshift is the redshift caused by scattering from his hot plasma. It is not intrrinsic to the galaxy. It would depend on the amount of plasma that the light passes through. A galaxy could have an intrinsic redshift of zero but his fantasy could have us measure a non-zero redshift.
No sensible person (or at least one who knows English) would call Brynjolfsson's plasma redshift intrinsic. My hope is that this is a really bad translation error.

Don J
2012-May-18, 03:39 AM
That is only one of the many things that Brynjolfsson gets wrong!
His 'intrinsic' redshift is the redshift caused by scattering from his hot plasma. It is not intrrinsic to the galaxy. It would depend on the amount of plasma that the light passes through. A galaxy could have an intrinsic redshift of zero but his fantasy could have us measure a non-zero redshift.
No sensible person (or at least one who knows English) would call Brynjolfsson's plasma redshift intrinsic. My hope is that this is a really bad translation error.
I expected something more in the line that he falsely claim that his plasma redshift mechanism may have something to do with an intrinsic redshift of Galaxies because that is impossible by the laws of physics....here the paper showing his math wrong .
But...
Come on you will not say that i have badly quoted again?Not only that he say that his plasma redshift mechanism predict an intrinsic redshift for Galaxies but also for Supernova,Quasars and stars.

Redshift of photons penetrating a hot plasma

http://arxiv.org/abs/astro-ph/0401420

I include the full abstract text that way you will not say that I have quoted badly this time.


A new interaction, plasma redshift, is derived, which is important only when photons penetrate a hot, sparse electron plasma. The derivation of plasma redshift is based entirely on conventional axioms of physics. When photons penetrate a cold and dense plasma, they lose energy through ionization and excitation, Compton scattering on the individual electrons, and Raman scattering on the plasma frequency. But in sparse hot plasma, such as in the solar corona, the photons lose energy also in plasma redshift. The energy loss per electron in the plasma redshift is about equal to the product of the photon's energy and one half of the Compton cross-section per electron. In quiescent solar corona, this heating starts in the transition zone to the corona and is a major fraction of the coronal heating. Plasma redshift contributes also to the heating of the interstellar plasma, the galactic corona, and the intergalactic plasma. Plasma redshift explains the solar redshifts, the redshifts of the galactic corona, the cosmological redshifts, the cosmic microwave background, and the X-ray background. The plasma redshift explains the observed magnitude-redshift relation for supernovae SNe Ia without the big bang, dark matter, or dark energy. There is no cosmic time dilation. The universe is not expanding. The plasma redshift, when compared with experiments, shows that the photons' classical gravitational redshifts are reversed as the photons move from the Sun to the Earth. This is a quantum mechanical effect. As seen from the Earth, a repulsion force acts on the photons. This means that there is no need for Einstein's Lambda term. The universe is quasi-static, infinite, and everlasting.

Reality Check
2012-May-18, 04:03 AM
I include the full abstract text that way you will not say that I have quoted badly this time.
This is only one of the many things that Ari Brynjolfsson gets wrong (not you)!
It is simple English. A redshift that is intrinsic to a galaxy is caused by the galaxy. If you remove the hot plasma that Brynjolfsson requires for redshift then there is no redshift. Thus Brynjolfsson's redshift is not intrinsic.

You should also read what you quote, note that the term intrinsic redshift does not appear there and what he actually writes:

A new interaction, plasma redshift, is derived, which is important only when photons penetrate a hot, sparse electron plasma. ...

But I did not read this cranks fantasy closely enough!
He says that "But in sparse hot plasma, such as in the solar corona, the photons lose energy also in plasma redshift.". So he is implying that his "plasma redshift" actuall happens in stars. But that means that we should observe stars in the Milky Way traveliing at high z!
The pre-print this up: He explicitly mentions the intergalactic plasma in section "5.8 Cosmological redshift".

Don J
2012-May-18, 04:58 AM
This is only one of the many things that Ari Brynjolfsson gets wrong (not you)!
It is simple English. A redshift that is intrinsic to a galaxy is caused by the galaxy. If you remove the hot plasma that Brynjolfsson requires for redshift then there is no redshift. Thus Brynjolfsson's redshift is not intrinsic.

Galaxies are made of stars which are made of hot plasma, so his plasma redshift apply.


You should also read what you quote, note that the term intrinsic redshift does not appear there ...

I have pointed to another paper (post 151)where he use the term intrinsic redshift of galaxies


... and what he actually writes:


A new interaction, plasma redshift, is derived, which is important only when photons penetrate a hot, sparse electron plasma. ...

But I did not read this cranks fantasy closely enough!
He says that "But in sparse hot plasma, such as in the solar corona, the photons lose energy also in plasma redshift.". So he is implying that his "plasma redshift" actuall happens in stars. But that means that we should observe stars in the Milky Way traveliing at high z!

Obviously you have not read the paper.
Where does he says that the stars in our Galaxy have a high z ?
http://arxiv.org/abs/astro-ph/0401420



The pre-print this up: He explicitly mentions the intergalactic plasma in section "5.8 Cosmological redshift".

In the sense that the intergalactic plasma also as an effect.

tusenfem
2012-May-18, 06:56 AM
Galaxies are made of stars which are made of hot plasma, so his plasma redshift apply.



Okay, Don J, if you want to defend the crank ideas of Brynjolffson, then take it to ATM, not here.
I don't see this anymore as "just asking questions and debating" which we were allowing up to now, I now see it as promotion.

parejkoj
2012-May-18, 02:45 PM
Since I originally proposed the idea in this thread, I'm noting my new "BAUT Supernova Challenge" here for people to check out. Come and give it a try. (http://www.bautforum.com/showthread.php/132654-The-BAUT-Supernova-Challenge)

Don J
2012-May-18, 07:17 PM
The change in SB of a galaxy as it ages is caused by the change in the stellar population and other factors. This is something that you can look up yourself.

However a quick Google gives this lecture: STELLAR POPULATIONS AND THE HISTORY OF THE UNIVERSE (http://www.astro.virginia.edu/class/oconnell/astr130/Spops-HistUniv.html)
Question about redshift.

Lets suppose we were actually living on one of these distant galaxies at high z lets say z=6 and look at the Milky Way from there ,does "astronomers " will observe our galaxy as having also the same high z ?Does the look back in time still apply ?

antoniseb
2012-May-18, 07:34 PM
... Lets suppose we were actually living on one of these distant galaxies at high z lets say z=6 and look at the Milky Way from there ,does "astronomers " will observe our galaxy as having also the same high z ?Does the look back in time still apply ?

An astronomer in a galaxy made of things we see now at z=6, but 13.7 billion years after the Big Bang in his setting, would see the bright star forming regions of things that came together to make our galaxy at z=6. I'm not sure what you're asking.

Don J
2012-May-18, 07:56 PM
An astronomer in a galaxy made of things we see now at z=6, but 13.7 billion years after the Big Bang in his setting, would see the bright star forming regions of things that came together to make our galaxy at z=6. I'm not sure what you're asking.

Your answser is right on the target.Do they will also see our Galaxy as having a high surface brightness ?
I ask this because...
I see that there are two type of stars formation rate in Galaxies:
from the link provided by Reality Check
http://www.astro.virginia.edu/class/oconnell/astr130/Spops-HistUniv.html


Stars are formed continuously in some galaxies, and only in bursts in others.

So, why do we observe only high z galaxies with high surface brithness ? There should be a noticable difference in the luminosity betwen galaxies at high z "which stars are formed continuously in some galaxies, and only in bursts in others."?

Cougar
2012-May-18, 09:20 PM
Do they will also see our Galaxy as having a high surface brightness ?

Do you really want to be talking about surface brightness, or do you want to be talking about angular extent, which is much more interesting in this context?

Don J
2012-May-19, 01:31 AM
Do you really want to be talking about surface brightness, or do you want to be talking about angular extent, which is much more interesting in this context?

Both subject are open to discussion!

Reality Check
2012-May-21, 12:46 AM
Galaxies are made of stars which are made of hot plasma, so his plasma redshift apply.

Obviously you have not read the pre-print since he explicitily includes only interegalactic plasma in his cosmological redshift section. Therefore his calculation is not intrinsic to galaxies.

For the cosmological redshifts, the first term on the right side in Eq. (20) is usually large compared with the second term on the right side. In Eq. (18), therefore, we can usually in the extended plasmas of space set F1 (a) = 1, because the intergalactic plasma is usually very hot and the electron density very low. We can also set γ = γ, because the redshifts are relatively large compared with the initial photon width.
and then equation 47.



Where does he says that the stars in our Galaxy have a high z ?

He does not. I never said that he did.
You are the one implying this by insisting that his misuse of "intrinsic" means that the redshift is generated by the galaxy, e.g. the stars. Interstellar plasma would also have an effect but then we would see stars in the Milky Way at higher and higher z as we look further and further away.

Another reason that it is obvious that you have not read his pre-print carefully is that you have missed the high school science mistake in equation 47. The left hand side is dimensionless. The right han side has units of inverse length squared!

TooMany
2012-May-22, 04:59 AM
Another reason that it is obvious that you have not read his pre-print carefully is that you have missed the high school science mistake in equation 47. The left hand side is dimensionless. The right han side has units of inverse length squared!

Wow, this guy must be really dumb to get his high school science wrong.



In 1973, he received a Doctor Philosophiae (DSc) from the Niels Bohrs Institute, University of Copenhagen.


But then again, anyone can make a dumb mistake.

Shaula
2012-May-22, 05:04 AM
Wow, this guy must be really dumb to get his high school science wrong.
No one except you said that. Reality check said it was a high school mistake - we all make them. Heck I've had a paper published that had what was probably a primary school mistake in. Was my face red when I caught it a year or two later! Although not as red as the reviewers.

TooMany
2012-May-22, 03:57 PM
No one except you said that. Reality check said it was a high school mistake - we all make them.

Previously tusenfem mentioned "the crank ideas of Brynjolffson". Reality Check seems to be suggesting that he has found evidence that the paper is by a crank. I can neither defend nor condemn his paper because I don't have that ability. However I'm curious about how his ideas are known to be "crank". Being quite suspicious myself, I looked into his background and history and saw nothing there to suggest that he was just some crank. In 1988 he won the Radiation Science and Technology Award of the American Nuclear Society (which I verified). "This award recognizes outstanding creative applications of radiation sciences and engineering principles." He does have a PhD in nuclear physics and is apparently a radiation specialist.

On the other hand, I didn't find (probably I haven't looked hard enough) a detailed refutation of his ideas about a plasma red shift.


Heck I've had a paper published that had what was probably a primary school mistake in. Was my face red when I caught it a year or two later! Although not as red as the reviewers.

Did your mistake invalidate the conclusions of your paper?

How carefully do reviewers actually review? It doesn't seem possible that they could verify every equation and calculation, so I suppose they have to be satisfied if 1) it contains no obvious mistakes and perhaps 2) makes no unusual claims. I would expect (and I think it's justifiable) that if a paper makes unusual claims it will receive deeper scrutiny, if publication is seriously considered.

Shaula
2012-May-22, 05:31 PM
Did your mistake invalidate the conclusions of your paper?
Nope, but they did invalidate the numerical predictions I had made.


How carefully do reviewers actually review? It doesn't seem possible that they could verify every equation and calculation, so I suppose they have to be satisfied if 1) it contains no obvious mistakes and perhaps 2) makes no unusual claims. I would expect (and I think it's justifiable) that if a paper makes unusual claims it will receive deeper scrutiny, if publication is seriously considered.
Which is pretty much what has been said all along. Some people seem to mistake this as a frozen mindset, or hostility to change.

tusenfem
2012-May-22, 05:38 PM
On the other hand, I didn't find (probably I haven't looked hard enough) a detailed refutation of his ideas about a plasma red shift.


The fact that he never pubished his stuff in a peer-reviewed journal speaks volumes.

Reviewers of theoretical papers will have to follow the equations and derivations, and hopefully spot mistakes if there are any.
Reviewers of data analysis papers will have to judge if the analysis methods are correct, and I have spotted enough bad analysis methods in the paper I reviewed.

Cougar
2012-May-22, 05:47 PM
How carefully do reviewers actually review? It doesn't seem possible that they could verify every equation and calculation, so I suppose they have to be satisfied if 1) it contains no obvious mistakes and perhaps 2) makes no unusual claims.

Your supposition would be incorrect. As tusenfem stated, a reviewer goes through a paper with a fine-toothed comb, verifying every equation and calculation.

TooMany
2012-May-22, 10:48 PM
The fact that he never pubished his stuff in a peer-reviewed journal speaks volumes.

Reviewers of theoretical papers will have to follow the equations and derivations, and hopefully spot mistakes if there are any.
Reviewers of data analysis papers will have to judge if the analysis methods are correct, and I have spotted enough bad analysis methods in the paper I reviewed.

Well I don't know if they were submitted and, if they were, whether they were actually reviewed in the detail suggested in the last post. You firmly declare him a "crank". Is that mostly based on his failure to publish or have you actually seen expert evaluations of his math and methods? What have you spotted wrong?

Reality Check
2012-May-22, 11:31 PM
Wow, this guy must be really dumb to get his high school science wrong.
But then again, anyone can make a dumb mistake.
I did not say that he was dumb.
I said that he made a mistake that a high school student should not make. That mistake was to not check his units. You do not need a high level of science understanding to know that an equation that says that a unit-less quantity (the red shift z) has units is wrong.

Curriculum Vitae for Ari Brynjolfsson (http://www.plasmaredshift.org/Curriculum_Vitae.html)
When you have someone who proposes an idea in pre-prints that show not sign of ever been published in a peer-reviewed journal since 2005 (http://www.plasmaredshift.org/Article_Archive.html) then you may have a crank.
When you have someone who states that he got this idea in 1978 and he does not cite his papers for it then you may have a crank.
When you have somone who has an idea that is physically impossible (a tired light theory) then you may have a crank.
When you have somone who makes basic mistakes in their pre-prints then you may have a crank.

And when you have multiple signs that a person may be a crank then he is a crank!

Reality Check
2012-May-22, 11:35 PM
Well I don't know if they were submitted and, if they were, whether they were actually reviewed in the detail suggested in the last post. You firmly declare him a "crank". Is that mostly based on his failure to publish or have you actually seen expert evaluations of his math and methods?
They were not according to him. (http://www.plasmaredshift.org/Article_Archive.html)
You seem to have missed:

Plasma Redshift Cosmology Fails (http://forums.randi.org/showthread.php?postid=7393901#post7393901) by Tim Thompson
The math errors in the pre-print (http://forums.randi.org/showthread.php?postid=7393481#post7393481) by ben m

This is also a "tired light" cosmology so Ned Wright's Errors in Tired Light Cosmology (http://www.astro.ucla.edu/~wright/tiredlit.htm) web page is applicable.
and that he makes a high school science mistake.

ETA: It is possible that the numeric factor in his equation 47 actually includes some units since it seems to be related to the classical electron radius.
However the next assumption is wrong - the electron density is not "nearly constant". Neutral hydrogen is ionized by light from galaxies so a photon from a distant galaxy will encounter increasing density of electrons as it travels to us.

Don J
2012-May-23, 03:51 AM
ETA: It is possible that the numeric factor in his equation 47 actually includes some units since it seems to be related to the classical electron radius.

Interesting observation.


However the next assumption is wrong - the electron density is not "nearly constant".

Note the "if"at the beginning of the assumption.From equation 48 he derive the average electron density (the sum of electron and positron density )in the intergalactic space ...


Neutral hydrogen is ionized by light from galaxies so a photon from a distant galaxy will encounter increasing density of electrons as it travels to us.

I really doubt that he don't take into account the ionization of the intergalactic space medium because it is in fact the basics of his plasma redshift theory.
Equation 47 is in page 43 of the pdf paper chapter 5.8 about Cosmological redshift . Dont forget also chapter 5.7 about Galactic Corona in page 36.

http://arxiv.org/abs/astro-ph/0401420

Reality Check
2012-May-23, 04:03 AM
I really doubt that he don't take into account the ionization of the intergalactic space medium because it is in fact the basics of his plasma redshift theory.

What he did not take in account is the increasing ionization of the intergalactic medium as his photons travel through it. That invalidates his assumption that the density of electrons is "nearly constant". It should vary from nearly zero at z > 6 (Gunn-Peterson trough) to local values (z=0).

ETA: Every time that I look at his pre-print I see more problems!
He claims that his idea explains the redshift of Fraunhofer lines from the Sun. This is usually explined by gravitational redshift. The problem is that we have experimentally confirmation that gravitational redshift exists, e.g. Pound–Rebka experiment in 1959. Therefore the redshift of Fraunhofer lines is evidence that his idea is invalid because his "plasma redshift" is not observed!

Don J
2012-May-23, 04:27 AM
What he did not take in account is the increasing ionization of the intergalactic medium as his photons travel through it. That invalidates his assumption that the density of electrons is "nearly constant". It should vary from nearly zero at z > 6 (Gunn-Peterson trough) to local values (z=0).

The more the distance traveled by the photons then more interaction occur betwen photons and electrons .Have you see the average electrons density from equation 49.



ETA: Every time that I look at his pre-print I see more problems!
He claims that his idea explains the redshift of Fraunhofer lines from the Sun. This is usually explined by gravitational redshift. The problem is that we have experimentally confirmation that gravitational redshift exists, e.g. Pound–Rebka experiment in 1959. Therefore the redshift of Fraunhofer lines is evidence that his idea is invalid because his "plasma redshift" is not observed!
He give details in
Chapter 5.6.3 page 32 of the pdf

Reality Check
2012-May-23, 04:36 AM
The more the distance traveled by the photon the more interaction occur betwen photons and electrons .

There is no mention of this in the pre-print.


Have you see the average electron density from equation 49.

There is no average electron density in equation 49. Ne is a function of distance (the dx being integrated over).
He has to make the incorrect assimption that Ne(x) is nearly constant in order to do the integration.

The details in Chapter 5.6.3 page 32 are not about gravitational redshift.
In chapter 7.2 he tries to throw away gravitational redshift and makes some quite ignorant statements, e.g. that the QM uncertainty relation invalidates the Pound–Rebka etc. experiments. He also gets the basics wrong such as Einstein derived gravitational redshift from the equivalence principle not Ari Brynjolfsson's fantasy of "Einstein’s two assumptions".

TooMany
2012-May-23, 05:13 AM
I did not say that he was dumb.
I said that he made a mistake that a high school student should not make. That mistake was to not check his units. You do not need a high level of science understanding to know that an equation that says that a unit-less quantity (the red shift z) has units is wrong.

Curriculum Vitae for Ari Brynjolfsson (http://www.plasmaredshift.org/Curriculum_Vitae.html)
When you have someone who proposes an idea in pre-prints that show not sign of ever been published in a peer-reviewed journal since 2005 (http://www.plasmaredshift.org/Article_Archive.html) then you may have a crank.
When you have someone who states that he got this idea in 1978 and he does not cite his papers for it then you may have a crank.
When you have somone who has an idea that is physically impossible (a tired light theory) then you may have a crank.
When you have somone who makes basic mistakes in their pre-prints then you may have a crank.

And when you have multiple signs that a person may be a crank then he is a crank!

So you don't need to actually read the paper with a full understanding of the subject. That's good to know. The next time a crank comes along I'll know without worrying about understanding anything.

Don J
2012-May-23, 05:18 AM
The details in Chapter 5.6.3 page 32 are not about gravitational redshift..

My error it is in Chapter 5.6.2 page 29
ETA


There is no average electron density in equation 49.

My bad i was not precise enough...
Read the line of text betwen equation 49 and equation 50 on page 43 of the pdf

TooMany
2012-May-23, 06:10 AM
Originally Posted by Reality Check
Plasma Redshift Cosmology Fails by Tim Thompson
The math errors in the pre-print by ben m


OK, I looked at these criticisms but I'm not sure I can verify them. If indeed he is a crank, then he is certainly one with a very elaborate story.

I'll reread Dr. Wright's argument that all tired light models are excluded since this one does seem to fall in that category.

Don J
2012-May-23, 06:20 AM
I'll reread Dr. Wright's argument that all tired light models are excluded since this one does seem to fall in that category.

Take note that in page 3 of the PDF the author mention -about what his plasma redshift is different of all the other to the point that this scattering process has never been dealt with before.-

http://arxiv.org/abs/astro-ph/0401420

tusenfem
2012-May-23, 06:36 AM
Well I don't know if they were submitted and, if they were, whether they were actually reviewed in the detail suggested in the last post. You firmly declare him a "crank". Is that mostly based on his failure to publish or have you actually seen expert evaluations of his math and methods? What have you spotted wrong?

They have not been peer reviewed, as you can easily find out from ADS.
As to the how and why, just go to the JREF links that Reality Check posted 1 or 2 pages ago, we need not repeat that whole discussion here.

tusenfem
2012-May-23, 06:39 AM
I really doubt that he don't take into account the ionization of the intergalactic space medium because it is in fact the basics of his plasma redshift theory.
Equation 47 is in page 43 of the pdf paper chapter 5.8 about Cosmological redshift . Dont forget also chapter 5.7 about Galactic Corona in page 36.


Okay that is ENOUGH with trying to make ATM look good in Astronomy.
The discussion of this paper is over or the alledged supporters of Brynjolffson can take to to the ATM section.
And no more linking to this paper in this thread!

Reality Check
2012-May-23, 10:20 PM
So you don't need to actually read the paper with a full understanding of the subject. That's good to know. The next time a crank comes along I'll know without worrying about understanding anything.
My point is that if anyone comes up with a hypothesis and then never publishes it in a peer-reviewed journal then that is a good sign that they are a crank.

Don J
2012-May-26, 03:43 AM
see post 9 for quote in context


Don J wrote:
Is it safe or (conceivable) to assume that there is a finite number of galaxies in an infinte Universe ?

It's doubtful that the universe is infinite.

I though that the BB cosmology state that the Universe is infinite ?


It's likely that the mass of all the matter in the universe is roughly constant

Is it possible that the amount of matter in the Universe is also finite ?
As Lavoisier stated:
"nothing is created, nothing is destroyed, everything is transformed"


The location of the mass seems to be changing as the voids slowly get less concentrated.

Interesting,is it the expansion of the Universe who is causing this?

BTW what is the effect of the expansion on the filamentary structure of the Universe does the expansion "stretch" the filamentary structure which cause that the voids gets less concentrated ?
http://www.cfht.hawaii.edu/News/Lensing/Images/Sliceshear.jpg

Don J
2012-May-26, 04:11 AM
Originally Posted by Don J
just that everything seem to be already set-up in term of creation of new galaxies forming from pristine primordial gas clouds.


Because they have had time to collapse - this is rather like being amazed that there are no babies being born in a retirement home.
Post 17

But not all of them have. Many have missed collapse so far. There are plenty of high velocity clouds around Milky Way, such as Smith´s Cloud, which is right now beginning a collision with Milky Way disc.

If there is plenty of high velocity clouds -around the- Milky Way it may be possible also that they exist around other Galaxies too=More baryonic matter.
http://en.wikipedia.org/wiki/Smith%27s_Cloud
I wondering if these high velocity clouds can produce the lensing effect which are attributed to cold dark matter ?
http://www.cfht.hawaii.edu/News/Lensing/


When a high velocity cloud hits galaxy disc, it creates a feature like Gould Belt. But what happens when two high velocity clouds hit each other away from any existing galaxy?
Probably this will produce only a bigger high velocity cloud rather than triggering the formation of a new galaxy.

Shaula
2012-May-26, 05:58 AM
I though that the BB cosmology state that the Universe is infinite ?
No it does not. It describes the evolution of the visible universe from a hot dense state. And that is all. Some properties of the visible universe (to do with the CMB) limit how small the universe could be.

Don J
2012-May-26, 06:20 AM
No it does not. It describes the evolution of the visible universe from a hot dense state. And that is all. Some properties of the visible universe (to do with the CMB) limit how small the universe could be.
Logically speaking that is what i though but it seem that astro.ucla edu differs about that and claim that the Universe is infinite based on the BIg Bang cosmology.

http://www.astro.ucla.edu/~wright/infpoint.html

Jeff Root
2012-May-26, 06:32 AM
The location of the mass seems to be changing as the
voids slowly get less concentrated.
I wondered at this when I first read it. First, by
"location" I would guess you mean "distribution".
"Location" seems an odd word choice.

The main question is what you mean by "the voids get
less concentrated." I'm quite sure you mean that they
get larger, because the galaxies which define the voids
by being around their edges are getting farther apart
from each other. So why "less concentrated"?

-- Jeff, in Minneapolis

Jeff Root
2012-May-26, 06:47 AM
Don,

That page of Ned Wright's explains how infinitely many dots
in an infinte mathematical universe could move apart in a way
similar to how we see the galaxies in the real Universe moving
apart. It really should not imply that the Universe is that way.

-- Jeff, in Minneapolis

Don J
2012-May-26, 06:54 AM
Don,

That page of Ned Wright's explains how infinitely many dots
in an infinte mathematical universe could move apart in a way
similar to how we see the galaxies in the real Universe moving
apart. It really should not imply that the Universe is that way.

-- Jeff, in Minneapolis
The confusing part is that it is suppose to be an answer to a Frequently Asked Questions in Cosmology:
How can the Universe be infinite if it was all concentrated into a point at the Big Bang?

http://www.astro.ucla.edu/~wright/cosmology_faq.html

Also the answer to the next question makes no doubt than he his talking about an infinite universe.

Is the Universe really infinite or just really big?

"We have observations that say that the radius of curvature of the Universe is bigger than 70 billion light years. But the observations allow for either a positive or negative curvature, and this range includes the flat Universe with infinite radius of curvature. The negatively curved space is also infinite in volume even though it is curved. So we know empirically that the volume of the Universe is more than 20 times bigger than volume of the observable Universe. Since we can only look at small piece of an object that has a large radius of curvature, it looks flat. The simplest mathematical model for computing the observed properties of the Universe is then flat Euclidean space. This model is infinite, but what we know about the Universe is that it is really big."

slang
2012-May-26, 07:58 AM
Also the answer to the next question makes no doubt than he his talking about an infinite universe.

Is the Universe really infinite or just really big?

"We have observations that say that the radius of curvature of the Universe is bigger than 70 billion light years. But the observations allow for either a positive or negative curvature, and this range includes the flat Universe with infinite radius of curvature. The negatively curved space is also infinite in volume even though it is curved. So we know empirically that the volume of the Universe is more than 20 times bigger than volume of the observable Universe. Since we can only look at small piece of an object that has a large radius of curvature, it looks flat. The simplest mathematical model for computing the observed properties of the Universe is then flat Euclidean space. This model is infinite, but what we know about the Universe is that it is really big."

No, Don J, the bolded part says something about a mathematical MODEL, not about the universe. The simplest model, even. And right after the part about the model, he answers what we know about the universe.

If Ken G were around he'd probably write a lengthy piece here about what science does, how it relates to reality, and he'd probably even dip a little into what "reality" means. Perhaps it's worth some time to hunt down some of his posts on the subject.

antoniseb
2012-May-26, 04:03 PM
I though that the BB cosmology state that the Universe is infinite ? ...
There have been a number of times that you've posted here saying "you thought" (or asked "Is it safe to say...") something commonly understood to be incorrect about current mainstream cosmological models. Yet you seem to have enough of a grasp of details that it seems likely that you never actually had that misconception. Are you making such statements just to stir things up? Or did you really think that current Big Bang models assume the universe is infinite in mass and volume?

Shaula
2012-May-26, 04:25 PM
Logically speaking that is what i though but it seem that astro.ucla edu differs about that and claim that the Universe is infinite based on the BIg Bang cosmology.

http://www.astro.ucla.edu/~wright/infpoint.html

Selective quoting - read their FAQ:


Is the Universe really infinite or just really big?

We have observations that say that the radius of curvature of the Universe is bigger than 70 billion light years ... So we know empirically that the volume of the Universe is more than 20 times bigger than volume of the observable Universe ... The simplest mathematical model for computing the observed properties of the Universe is then flat Euclidean space. This model is infinite, but what we know about the Universe is that it is really big.

Edit: I see you did and have found that bit that shows that BB cosmology does not require an infinite universe or predict one exclusively.

Don J
2012-May-26, 07:16 PM
Or did you really think that current Big Bang models assume the universe is infinite in mass

No


and volume?

That is that part that was not clear enough.But now that I know that the Big Bang model say that the volume of the Universe is finite that clears things up.

Don J
2012-May-26, 07:25 PM
Selective quoting - read their FAQ:
but what we know about the Universe is that it is really big.

Edit: I see you did and have found that bit that shows that BB cosmology does not require an infinite universe or predict one exclusively.
the part i have problem with is:


"The simplest mathematical model for computing the observed properties of the Universe is then flat Euclidean space. This model is infinite"

Why applying a mathematical model for an infinite Universe if the Universe is just really big but finite ?

antoniseb
2012-May-26, 07:36 PM
... Why applying a mathematical model for an infinite Universe if the Universe is just really big but finite ?
For the same reason we usually use Newtonian mechanics to calculate local low-speed things where high precision is not needed... it is easier, and gets the job done for certain tasks. You wouldn't use a flat Euclidean assumption for the hole universe, but it works pretty well for the Solar System.

Shaula
2012-May-26, 08:24 PM
Why applying a mathematical model for an infinite Universe if the Universe is just really big but finite ?
The answer to that is in the quote - to make the maths easier. Just like we use models with perfect resistors, circular orbits, point particles, flat spacetime, lossless transmission, conserved energy and many, many more simplifications that are used to make the calculations simpler. Usually they are good enough, or indistinguishable enough from more complex models for the predictions they are being used for.

Tensor
2012-May-27, 02:19 AM
Just like we use models with perfect resistors, circular orbits, point particles, flat spacetime, lossless transmission, conserved energy ...

I was waiting to see spherical cows in there somewhere. :)

Reality Check
2012-May-27, 09:24 PM
That is that part that was not clear enough.But now that I know that the Big Bang model say that the volume of the Universe is finite that clears things up.
You still have it wrong: The Big Bang model says nothing about whether the volume of the universe is finite or infinite.
What it says is that the observable part of the universe (which due to the finite speed of light is finite) was once in a hot dense state. It does not say anything about what is outside the observable universe. The observable universe can be part of a finite or infinite universe.

Don J
2012-May-28, 06:29 AM
You still have it wrong: The Big Bang model says nothing about whether the volume of the universe is finite or infinite.
What it says is that the observable part of the universe (which due to the finite speed of light is finite) was once in a hot dense state.

Observable Universe =what we can actually see from the Hubble Ultra Deep Field .... Galaxies at z=6 which formed about 1 billion years after the Big Bang.


It does not say anything about what is outside the observable universe.

What is it supposed to exist outside the observable Universe "empty" space without galaxies or we may have the surprise to find other galaxies but at z =6.5 ..... z=7 with better optical equipments ?


The observable universe can be part of a finite or infinite universe.

In other words... we don't know.

antoniseb
2012-May-28, 12:01 PM
Observable Universe =what we can actually see from the Hubble Ultra Deep Field .... Galaxies at z=6 which formed about 1 billion years after the Big Bang.
...
What is it supposed to exist outside the observable Universe "empty" space without galaxies or we may have the surprise to find other galaxies but at z =6.5 ..... z=7 with better optical equipments ?...

You have a habit of making wrong statements as though they were facts. In this case observable universe doesn't end at what has been already observed in the optical wavelengths. The term refers to everything that could be observed today with all possible technologies. It is not limited to today's technology. ... So then you take your wrong definition, and ask what happens if you extend it? Again, I'm pretty sure you know better. So many of your posts are written this way, I don't think you're asking from misunderstanding.


In other words... we don't know.
Right. Things seem to point to finite, but the models that we call "The Big Bang Theory" don't specifically depend on that answer. It is possible that future observations might be able to tell us more certainly. If something solid ever develops from String Theory (or LQG), we might have answers from that too. But for now, this is yet another brilliant puzzle that motivates the study of cosmology.

Tensor
2012-May-28, 05:31 PM
Observable Universe =what we can actually see from the Hubble Ultra Deep Field .... Galaxies at z=6 which formed about 1 billion years after the Big Bang.

We can't see the CMB in the Hubble deep field. Unless we were using COBE or WMAP (or a few other things) and that can be seen in other places as well. Are you saying the CMB doesn't count as an observation? And, there are other places beside the Hubble Deep Field for optical observations....


What is it supposed to exist outside the observable Universe "empty" space without galaxies or we may have the surprise to find other galaxies but at z =6.5 ..... z=7 with better optical equipments ?

How about z = 8.6 galaxy (http://arxiv.org/abs/1010.4312) with current equipment? Or how about a GRB at z = 9.4 (http://arxiv.org/pdf/1105.4915v3.pdf) with current equipment. Or, even a z = 10 candidate galaxy (http://arxiv.org/pdf/0912.4263v6.pdf) with current equipment. For someone who makes absolute pronouncements about cosmology, you seem not to know about a lot of the current papers that contradict your claims.

Don J
2012-May-28, 06:21 PM
We can't see the CMB in the Hubble deep field. Unless we were using COBE or WMAP (or a few other things) and that can be seen in other places as well. Are you saying the CMB doesn't count as an observation?

No ,i am not saying that ... see below




How about z = 8.6 galaxy (http://arxiv.org/abs/1010.4312) with current equipment? Or how about a GRB at z = 9.4 (http://arxiv.org/pdf/1105.4915v3.pdf) with current equipment. Or, even a z = 10 candidate galaxy (http://arxiv.org/pdf/0912.4263v6.pdf) with current equipment. For someone who makes absolute pronouncements about cosmology, you seem not to know about a lot of the current papers that contradict your claims.
The thing who came is mind is what would happend if galaxies were found with redshift so high that it put them in absolute time before the CMB emission ?

antoniseb
2012-May-28, 06:50 PM
No ,i am not saying that ... see below
The thing who came is mind is what would happend if galaxies were found with redshift so high that it put them in absolute time before the CMB emission ?

The CMB was at about z=1100... and it is sooo unlikely that galaxies would be seen in deep microwave before then that we don't need to discuss it. Is this possibility why you seem so against the mainstream?

Don J
2012-May-28, 07:15 PM
The CMB was at about z=1100... and it is sooo unlikely that galaxies would be seen in deep microwave before then that we don't need to discuss it.
Let see in absolute time a galaxie at z =10 make its creation at 300 to 500 millions years after the Big bang ....I dont think we need to find Galaxies at z=1100 before reaching a time when Galaxies formed at the approximate time of the Big Bang 13.5 billion years ago. The discovery of a galaxy at say z=15 or z=20 can do the work ?



Is this possibility why you seem so against the mainstream?
I am not against the mainstream...just questioning about possible future discovery.

Reality Check
2012-May-28, 11:13 PM
Observable Universe =what we can actually see from the Hubble Ultra Deep Field .... Galaxies at z=6 which formed about 1 billion years after the Big Bang.

Observable Universe = what we can actually see from any instrument, including Hubble, WMAP and Planck.

What exists outside of the observable universe is more universe containing stuff that we cannot observe.

What we can observe is the universe to very high z (~1100 for the CMB).
What we have done is detect galaxies to about z~10 (UDFj-39546284 (http://en.wikipedia.org/wiki/UDFj-39546284))

Reality Check
2012-May-28, 11:24 PM
The thing who came is mind is what would happend if galaxies were found with redshift so high that it put them in absolute time before the CMB emission ?
That is physically impossible. The CMB was released before the formation of stars when the universe was filled with a hydrogen plasma (thus the perfect black body spectrum). Thus any such detection would be an observational error.

antoniseb
2012-May-28, 11:30 PM
Let see in absolute time a galaxie at z =10 make its creation at 300 to 500 millions years after the Big bang ....I dont think we need to find Galaxies at z=1100 before reaching a time when Galaxies formed at the approximate time of the Big Bang 13.5 billion years ago....
Reality Check already has this covered pretty well, but let me just say explicitly that the amount of time between z values approaches zero as z goes toward infinity. z=1089 is about 380,000 years after the big bang. This is the time of deionization, which is also the time of the origin of the cosmic background radiation (which has been redshifted from visible and UV into the microwaves).

Jeff Root
2012-May-29, 03:03 PM
Tensor linked to http://arxiv.org/pdf/0912.4263v6.pdf

Near the beginning it says:



Not only do we find one possible z ≈ 10 galaxy candidate,
but we show that, regardless of source detections, the star
formation rate density is much smaller (∼10%) at this time
than it is just ∼200 Myr later at z ≈ 8. This demonstrates
how rapid galaxy build-up was at z ≈ 10, as galaxies
increased in both luminosity density and volume density
from z ≈ 8 to z ≈ 10.
I might learn further on in the PDF, but I don't recognize
the terms "luminosity density" and "volume density".
Could someone explain them?

In any case, the last two z values quoted seem backward.
Chronologically, of course, z ≈ 10 came before z ≈ 8.
Didn't galaxies increase in "luminosity density" and
"volume density" from z ≈ 10 to z ≈ 8 ?

-- Jeff, in Minneapolis

Don J
2012-Jun-08, 04:09 AM
from post 78
A non-expanding universe has been around forever so we run against Olbers' paradox.

Apparently based on this author demonstration...
Olber's paradox is solved.
Pdf
http://www.ronaldkoster.net/olber.pdf

Shaula
2012-Jun-08, 06:18 AM
Apparently based on this author demonstration...
Olber's paradox is solved.
Pdf
http://www.ronaldkoster.net/olber.pdf
Author knows little about radiation physics it appears. He 'solves' it by making matter absorb it according to Beers law. He ignore re-radiation or any other effects and treat the absorbed energy as totally gone. So in his 'solution' every atom is an infinite sink for energy. Can you see the problem with this? Did you read the pdf before you linked it?

Cougar
2012-Jun-08, 12:45 PM
Apparently based on this author demonstration...
Olber's paradox is solved.
Pdf
http://www.ronaldkoster.net/olber.pdf


"...there is a difference between an open mind and an open sink. The open mind allows for the critical examination of ideas, and it is receptive to new ones; the open sink is willing to accept anything and everything as worthy of examination without any responsible filtering process." -- Paul Kurtz

TooMany
2012-Jun-08, 02:35 PM
Author knows little about radiation physics it appears. He 'solves' it by making matter absorb it according to Beers law. He ignore re-radiation or any other effects and treat the absorbed energy as totally gone. So in his 'solution' every atom is an infinite sink for energy. Can you see the problem with this? Did you read the pdf before you linked it?

Is that an insurmountable problem? Suppose the energy just sinks into the vacuum rather like Dark Energy emerges from the vacuum, but with the opposite sign.

Shaula
2012-Jun-08, 03:56 PM
Is that an insurmountable problem? Suppose the energy just sinks into the vacuum rather like Dark Energy emerges from the vacuum, but with the opposite sign.
Why would that happen and why do we not see it in a lab? Why would we not see evidence of it spectroscopically? If it were a vacuum property then we would be into tired light territory and I don't think we need to go over the problems with that hypothesis again.

Yes it is an insurmountable problem.

Don J
2012-Jun-08, 07:06 PM
"...there is a difference between an open mind and an open sink. The open mind allows for the critical examination of ideas, and it is receptive to new ones; the open sink is willing to accept anything and everything as worthy of examination without any responsible filtering process." -- Paul Kurtz

That is why I was prudent and used the word -apparently- which means that I use a responsible filtering process.

Don J
2012-Jun-08, 07:16 PM
Author knows little about radiation physics it appears. He 'solves' it by making matter absorb it according to Beers law. He ignore re-radiation or any other effects and treat the absorbed energy as totally gone. So in his 'solution' every atom is an infinite sink for energy. Can you see the problem with this? Did you read the pdf before you linked it?
Quite frankly i was to lazy to fully read it before I linked it....but i was sure that i will know about the validity of the author claims one way or another.
I was rather tempted by giving my own take on the Olber's paradox which goes like this:
In the 19th century when Olber make his paradox astronomers did not know about Galaxies that is why his interpretation was that the night Sky needed to be patched full of stars in an eternal universe.

Shaula
2012-Jun-08, 09:40 PM
In the 19th century when Olber make his paradox astronomers did not know about Galaxies that is why his interpretation was that the night Sky needed to be patched full of stars in an eternal universe.
Why would that make a difference? In an infinite, eternal, static universe sooner or later every line of sight would hit a galaxy.

Please, before you use something to support one of your arguments, read it. It is a waste of our time and yours to have to point out the really, really obvious flaws in someone's unpublished thoughts on a topic.

Don J
2012-Jun-09, 01:27 AM
Why would that make a difference? In an infinite, eternal, static universe sooner or later every line of sight would hit a galaxy.

But that is exactly what the different Sky surveys have pointed out... right?
http://en.wikipedia.org/wiki/Sloan_Digital_Sky_Survey
http://en.wikipedia.org/wiki/2dF_Galaxy_Redshift_Survey



Please, before you use something to support one of your arguments, read it. It is a waste of our time and yours to have to point out the really, really obvious flaws in someone's unpublished thoughts on a topic.
Sorry for a moment of laziness. I know that it is unforgivable in science.
Remember that the topic was originally in the questions and answers thread so everything which followed was to clear some questions even if there was not always a (?) at the end.

antoniseb
2012-Jun-09, 01:47 AM
But that is exactly what the different Sky surveys have pointed out... right?
...
No. There may be numerous galaxies in every square arc-minute, but even looking at the Milky Way, you do not see the brightness of the Sun's surface on every square arc-minute. You see dim light. And distant galaxies are even dimmer and not filling all of space. ... and once again, I have to assume you knew this, and were only posting this argument out of some form of self-amusement.

Don J
2012-Jun-09, 03:45 AM
No. There may be numerous galaxies in every square arc-minute, but even looking at the Milky Way, you do not see the brightness of the Sun's surface on every square arc-minute. You see dim light. And distant galaxies are even dimmer and not filling all of space. ... and once again, I have to assume you knew this,
That is with the Olber's paradox that I have a problem with.
Based on recent conversations it seem that the Olber's paradox is based on the assumption that an eternal universe:
1-must be infinite.
2-must have enough matter to produce an infinity of galaxies in that -expected- infinite universe which must be packed so close together that the night sky must be luminous.

If so that does not make sense at all.

Tensor
2012-Jun-09, 04:32 AM
That is with the Olber's paradox that I have a problem with.
Based on recent conversations it seem that the Olber's paradox is based on the assumption that an eternal universe:
1-must be infinite.
2-must have enough matter to produce an infinity of galaxies in that -expected- infinite universe which must be packed so close together that the night sky must be luminous.

If so that does not make sense at all.

It's no wonder it makes no sense to you. The conditions you present as required for Olber's paradox, are not the conditions. Any simple query on google would have given you the proper conditions.

Shaula
2012-Jun-09, 06:05 AM
That is with the Olber's paradox that I have a problem with.
Based on recent conversations it seem that the Olber's paradox is based on the assumption that an eternal universe:
1-must be infinite.
2-must have enough matter to produce an infinity of galaxies in that -expected- infinite universe which must be packed so close together that the night sky must be luminous.

If so that does not make sense at all.
This page (http://en.wikipedia.org/wiki/Olbers%27_paradox) has a summary. Suggest you read it before arguing that the idea doesn't make sense.

TooMany
2012-Jun-09, 07:41 AM
Why would that happen and why do we not see it in a lab?

Well, if you are willing to be even handed toward conjectures (which is all this is), why don't we see DM in the lab? We can never see inflation in a lab (which is assumed new physics). It's unlikely that we can see Dark Energy (also new physics) in the lab.


Why would we not see evidence of it spectroscopically?

We do, the disappearing energy causes the redshift.


If it were a vacuum property then we would be into tired light territory and I don't think we need to go over the problems with that hypothesis again.

Do you mean Dr. Wright's problems? Dr. Wright has stated that any type of tired light theory has these "errors":

1) It's impossible, because no mechanism has been found.

There isn't a proven mechanism for inflation, DM is still undetected and Dark Energy is new to physics. Should we consider all of those impossible and dismiss them?

2) SN 1a data proves that there is time dilation.

Well, I think I'll wait and see on this one. No dilation has been found in quasar variations which have even larger redshifts.

3) It is not possible to produce a blackbody spectrum that way.

Here he seems to assume that there is no possible mechanism that can extract energy from starlight and produce from it a backbody spectrum.
This is similar to 1. Could there not be some mechanism? Is space absolutely perfectly transparent over 10s of millions or billions of light years so that there is no possible interaction with light?
Space contains a thin plasma in which particles have rather uniformly random motions over enough distance. Could not some interaction occur to produce a thermal spectrum from starlight?
Or perhaps the IGM or ICM contain solid particles which behave like black bodies. The starlight warms these particles to 2.7 K. This would explain the close approximation of Eddiington's "temperature of space" to the temperature of the CMB (which Dr. Wright asserts is just a coincidence).

4) Lubin & Sandage (2001) show that tired light fails this test [Tolman surface brightness] by 10 standard deviations.
This paper was disappointing given that it boldly sets out to show that expansion is the only possibility. In order to prove their conclusion, they introduced galactic evolution as an assumption which a priori requires a theory in which the galactic population of the universe changes over time. Here is the key to the 10 sigma argument:


The crucial question is whether it [surface brightness depression for tired light] is so much smaller as to conform to a depression of only 2.5 log (1 + z) mag [as in some tired light models] when the correction for luminosity evolution is also applied.

With all due respect to Dr. Wright, he should not make such an unqualified assertion about tired light when it is said to fail because it contradicts the authors' evolution theory.


Yes it is an insurmountable problem.

Surely no more so than the currently favored new physics.

Of course I will admit that expansion theory has had many successes, but there are a lot of issues that it still needs to address.

Shaula
2012-Jun-09, 10:48 AM
Well, if you are willing to be even handed toward conjectures (which is all this is), why don't we see DM in the lab? We can never see inflation in a lab (which is assumed new physics). It's unlikely that we can see Dark Energy (also new physics) in the lab.
The hypothesis was that ATOMS were acting as sinks. They were using the Beer-Lambert law for attenuation so it has to be at an atomic scale. So it should show up in a lab. DM is not a new process, but a material. The dynamics of it are well explained by gravity... Which we do see in a lab. As for expansion - different scale, weak effect.


We do, the disappearing energy causes the redshift.
No mechanism for that exists that would reproduce the redshift and the observations we make.


With all due respect to Dr. Wright, he should not make such an unqualified assertion about tired light when it is said to fail because it contradicts the authors' evolution theory.
I note you ignored the two points at the start of the page which are real killers of the tired light idea. Time dilation (tired light cannot do this) and Blurring (tired light must do this or you are breaking QM). So now you are saying that his counterpoints are poor because they ignored the fact that if you propose a range of utterly new processes that flatly contradict our most successful theories (QED especially) and require us to be in a special place in the universe, or space to have some wild properties, he is wrong?

And proven mechanisms for expansion? There are several proposed. The problem is that to prove them we need to put the universe into a false vacuum state. That is a bit hard to do.


Surely no more so than the currently favored new physics.
Yes, it is far more problematic to try to shoehorn our observations and theories into a tired light box. Truth is it just does not work. No tired light model of the universe has come close to working. No tired light or eternal static model has had even a quarter of the predictive power of the current model. You may not like this, you may try to rebel against it and poke holes in it but you cannot win this argument without a good alternative. There is none. There have been none. Lot of people have tried and failed. What does this tell you?

Cougar
2012-Jun-09, 01:58 PM
Do you mean Dr. Wright's problems?

Why do you say they are just Dr. Wright's problems? Are you trying to mislead people - and yourself - into thinking that it's only Dr. Wright who has problems with the failed tired light conjecture? Actually, Dr. Wright has simply summarized the position of the entire scientific community (minus a few misguided diehards).


1) It's impossible, because no mechanism has been found.

Like so many of the statements you have offered up on these boards, this is just wrong and misleading.


There isn't a proven mechanism for inflation, DM is still undetected and Dark Energy is new to physics. Should we consider all of those impossible and dismiss them?

Those are distinguishable from tired light. This "argument" is also a bit like "But he hit me first."


2) SN 1a data proves that there is time dilation.
Well, I think I'll wait and see on this one.

Wait for what? The data is available. What are you waiting for? Why do you think anyone would be interested in your thoughts on topics that you obviously know nothing about?


No dilation has been found in quasar variations which have even larger redshifts.

Quasar variations are extremely poor phenomena from which to try to detect time dilation. And you probably have no idea why. Why do you think anyone would be interested in your thoughts on topics that you obviously know nothing about?


With all due respect to Dr. Wright, he should not make such an unqualified assertion about tired light when it is said to fail because it contradicts the authors' evolution theory.

With all due respect? You are giving Dr. Wright none of the respect he is due. Perhaps you would provide us with your qualifications and academic accomplishments and compare those with Dr. Wright's? Perhaps you could compare the number of years you have studied physics, astronomy, astrophysics and cosmology, and compare that with the number of years Dr. Wright has worked in those fields?

May I suggest that your approach to learning has a rather serious defect? It appears that you question the efficacy of strongly supported findings before you know anything about them or understand why they are strongly supported. This is why people tend to respond to your statements none too kindly. A better approach, and the way most people do it, is to study first and find out something about your topic of interest, THEN ask questions if you have any doubts about methodologies or whatever. Typically, when people have done some studying and research and they know something about these topics, they understand what the observational support is and why the mainstream have settled on a particular position. And btw, mainstream scientists understand that NO position is set in stone. However, if an idea is well-supported and observationally repeated and confirmed, it takes a lot more to modify a position than, for example, the irrational skepticism of an upstart high school junior whose entire background on the subject amounts to a two-week section from his general science class.

tusenfem
2012-Jun-09, 02:41 PM
Well, if you are willing to be even handed toward conjectures (which is all this is), why don't we see DM in the lab? We can never see inflation in a lab (which is assumed new physics). It's unlikely that we can see Dark Energy (also new physics) in the lab.

... snip ...



TooMany, take this to ATM if you want to fight mainstream theory. Apparently you think we cannot test this "atomic sink" idea of some guy on the internet, so in ATM you will have your chance to defend this stance.
Similarly your ideas about how the black body spectrum of the CMBR is created seems well outside the mainstream ideas, so take it to ATM if you want to discuss this.
Nor does your apparent approval of some kind of tired light theory fit anywhere else as in ATM.
Any other place discussing this will lead to an infraction.

TooMany
2012-Jun-09, 04:16 PM
TooMany, take this to ATM if you want to fight mainstream theory. Apparently you think we cannot test this "atomic sink" idea of some guy on the internet, so in ATM you will have your chance to defend this stance.
Similarly your ideas about how the black body spectrum of the CMBR is created seems well outside the mainstream ideas, so take it to ATM if you want to discuss this.
Nor does your apparent approval of some kind of tired light theory fit anywhere else as in ATM.
Any other place discussing this will lead to an infraction.


I said a "vacuum sink", an analogy to the "vacuum source" of DE. You are not really paying attention here; you are only detecting a threat.

I'm not so much fighting mainstream theory but rather trying to generate discussion of alternative possibilities. I now realized (duh, I'm sure slow to catch on) that this is really not an option on this forum. It's not at all what this forum is about.

This forum is not about discussing science, it is nothing more than a platform for some self-anointed priests to disseminate a dogma and protect it from the heretics. ATM is where, with your missionary zeal, you stone the heretics until they submit to the dogma. That's rather disappointing.

Actually I didn't know anything about this forum and how the moderators were selected. I finally just found some info in the wiki. Who is Fraser Cain? Does he personally elect all the moderators?

Interesting: "Live Casting: Bringing Astronomy to the Masses in Real Time" rather like "spreading the word".

Oh well, it is what it is and you are the proprietors, so best of luck with your mission.

parejkoj
2012-Jun-09, 04:34 PM
I'm curious what those who insist that all astronomical observations must be verified in the lab think about our observations of 21cm emission in other galaxies and the 500.7nm narrow emission line in some nebula and galaxies. Neither of these lines has ever been produced in a lab setting, nor do we have any feasible mechanism to create them in any currently imagined lab. Does that mean that they are not produced by the spin-flip transition of atomic Hydrogen and the 1D2->3P transition of doubly-ionized Oxygen, respectively?

Also, TooMany, if you think that this forum has any real bearing on astronomical results, I've got a bridge to sell you. People come here to talk about things that interest them, and I think maybe one peer-reviewed paper was written via a collaboration created on this forum. But there's a very good reason that the ATM section is what it is: nearly all proponents of ATM theories have neither the math nor the physics background to understand most objections to their ideas, let alone to fully flesh their own ideas out. Words don't get you far in astrophysics: quantitative predictions do.

tusenfem
2012-Jun-09, 05:09 PM
I said a "vacuum sink", an analogy to the "vacuum source" of DE. You are not really paying attention here; you are only detecting a threat.

I'm not so much fighting mainstream theory but rather trying to generate discussion of alternative possibilities. I now realized (duh, I'm sure slow to catch on) that this is really not an option on this forum. It's not at all what this forum is about.

This forum is not about discussing science, it is nothing more than a platform for some self-anointed priests to disseminate a dogma and protect it from the heretics. ATM is where, with your missionary zeal, you stone the heretics until they submit to the dogma. That's rather disappointing.

Actually I didn't know anything about this forum and how the moderators were selected. I finally just found some info in the wiki. Who is Fraser Cain? Does he personally elect all the moderators?

Interesting: "Live Casting: Bringing Astronomy to the Masses in Real Time" rather like "spreading the word".

Oh well, it is what it is and you are the proprietors, so best of luck with your mission.

There can well be discussion of physics, there are numerous threads here on this board, however, you always push the ATM points of view, even though you apparently do not have the knowledge nor the skills to actually support your claims. This does not keep you from claiming that these ATM views are solid, never mind whether they published on a personal website or in an actual reviewed journal.

Also, there is no "vacuum sink" there was talk about absorption by ATOMS in the paper, and there most certainly is no "vacuum source" of DM, whatever that may be.

If you want to know how moderators are created, then I can tell you. I was asked, after many years of membership and discussions, by an administrator, when they wanted to increase the number of moderators again after several stepped down because of various reasons. I assume that they looked at my discussions, at my scientific qualifications (PhD in plasma astrophysics, (co)author on ~130 peer reviewed papers, etc.). And you may think my main job is to "control mainstream" here on BAUT, however, most of the time goes into banning spammers trying to sell handbags etc.

And no, we do not stone heretics in ATM, we give people the possibility to present their case and defend it against the scrutiny of (knowledgable) BAUT members. However, while you neither have the skills nor the knowledge necessary to defend anything concerning something that contradicts mainstream physics, you might quickly feel overwhelmed by the comments that people make who know what the are actually talking about.

However, nobody is forcing you to stay here, there are many other boards where you may discuss this kind of stuff, but I must say that BAUT is one of the nicer ones, but take a look around at e.g. JREF or tommac's board.

neilzero
2012-Jun-09, 05:18 PM
If ten new galaxies were in early stages of formation within one million light years of Earth, how could we tell, as it takes a million plus years for a medium size galaxy to form. Perhaps a galaxy soon to have 1000 stars, could gain a star per century which might be noticeable comparing 130 year old high magnification photo graphic plates with recent images. I don't think anyone would consider 1000 stars a galaxy; about a billion stars is minimum, but perhaps esentially the same thing is happening much smaller scale = 1000 stars. Neil

Cougar
2012-Jun-09, 10:49 PM
This forum is not about discussing science, it is nothing more than a platform for some self-anointed priests to disseminate a dogma and protect it from the heretics. ATM is where, with your missionary zeal, you stone the heretics until they submit to the dogma.

Ha ha. I haven't had time to hang out in ATM lately. These are virtual stonings, I presume. Sounds like we have a disgruntled gladiator. Give this man his money back.

TooMany
2012-Jun-10, 03:34 AM
There can well be discussion of physics, there are numerous threads here on this board, however, you always push the ATM points of view, even though you apparently do not have the knowledge nor the skills to actually support your claims. This does not keep you from claiming that these ATM views are solid, never mind whether they published on a personal website or in an actual reviewed journal.


I'm not an expert and you are; that is true. I was a physics major turned math major many, many years ago. My gripe is not that you want to keep truly cuckoo ideas out of regular discussions and isolate them to an ATM section. My gripe is that any deviation from the current interpretation of observations by the "mainstream" is treated as cuckoo. Alternate ideas are thoroughly condemned in a hostile, defensive style. Sorry, but the impression it gives is rather like in faiths where the believers will condemn any information not consistent with their beliefs as incorrect or impossible. At least that's what I sense generally from the regulars here.



Also, there is no "vacuum sink" there was talk about absorption by ATOMS in the paper, and there most certainly is no "vacuum source" of DM, whatever that may be.


Here you have given me an example. If you actually bothered to read what I was suggesting, it goes something like this. If DE (Dark Energy) (not DM - Dark Matter) can emerge from the vacuum (new physics). I'm suggesting (using the same license) that alternatively it might be possible for some of the energy of light to sink into the vacuum (also new physics). Either idea is about equally unusual in terms of known physics. Such a sink could account for the redshift and avoid the problem of ATOMS re-emitting in the paper under discussion. This idea would also solve Oblers' paradox. Yada yada. It was just an alternate suggestion. So you see, in your rush to condemn my idea, you didn't even bother to get it right by reading what I actually said.

I have no proof of this theory; I just made up, but my point is that when you try to explain observations there may be many possibilities. The astronomical community has latched onto one particular explanation and excluded others of any sort. Hubble himself was never satisfied with the expansion explanation, but others were and that explanation is now assumed to be true almost like gospel for fifty years.

There are problems with LCDM, but whenever I attempt to discuss one in this forum, what happens is a bunch of members swoop down to stamp out the problem. In fact this is what many mainstream papers do today. They defend LCDM by trying to come up with explanations that make non-conforming observations go away. If a member can find such a paper (and whatever the issue is you can find one), that paper must be correct and therefore the issue raised by the observation is resolved. This is an interesting pattern. It is used to close off the discussion of non-conforming observations or to force the discussion into the ATM where members can blame you for not having a complete alternate theory of cosmology to replace the existing one. Isn't that a rather steep requirement in order to be allowed to discuss non-conforming observations?

Astronomy has gotten very exciting in the last decade or two, because instruments are getting close to being able to actually see details at high z. Many things seen have been very surprising and are not what was predicted by CDM theory (but it somehow quickly adapts). Also, in the local universe several problems have been encountered with DM (other than no direct detection). Contrary observations are often noted as "tension" in mainstream papers. The mainstream writes papers that make arguments to relieve some of this "tension". If they can get the tension down to about 1 sigma with various assumptions, they can pretty much call the problem solved and members here are quite satisfied.

In this forum, members and administrators create a pretense that everything is settled; the theory is correct, period. Quite confidently we know the universe is 13.7 billions years old, 73% DE, 13% DM and that a mere 4% is the only type of matter that we actually know exists.

Above I was told that all tired light theories are proven false. I've done quite a lot of reading and I'm well aware of Dr. Wrights renown and his backing of LCDM. I've read his very nice explanations of the theory for novices. I wanted to address his claims of tired light models "proven false" because I found them a bit shoddy. But every counter argument I made regarding Dr. Wright's web page on this subject must be wrong. There is absolutely not the slightest bit of doubt about this. I claim however that most of his arguments a very weak and I pointed out why. The only one that is truly based on observation is the claim that SN 1a curves show time dilation. Not everyone in the field is convinced of this. Many think we simply don't yet have enough knowledge about these events or what the true magnitudes are in order to conclude this (selection effects, extinction etc.) On the other hand, there has been an analysis of the fluctuations of quasars that statistically demonstrate that no time dilation is observed (even the author observes that since time dilation must exist, the fluctuations must be caused by micro lensing by unknown foreground objects). Yet I'm told by a member that this paper does not hold water. The SN evidence is much stronger, event though quasars have redshifts 5 times that of the SN studied.

What I'm saying is that your members and administrators do not treat contrary information fairly, they just react defensively. As soon as I make any argument at all that cast any doubt on the mainstream theory I must go to the ATM forum with most of the kooks.



If you want to know how moderators are created, then I can tell you. I was asked, after many years of membership and discussions, by an administrator, when they wanted to increase the number of moderators again after several stepped down because of various reasons. I assume that they looked at my discussions, at my scientific qualifications (PhD in plasma astrophysics, (co)author on ~130 peer reviewed papers, etc.). And you may think my main job is to "control mainstream" here on BAUT, however, most of the time goes into banning spammers trying to sell handbags etc.


Thanks for that. You do such a good job with the spamming that I've never seen any!



And no, we do not stone heretics in ATM, we give people the possibility to present their case and defend it against the scrutiny of (knowledgable) BAUT members. However, while you neither have the skills nor the knowledge necessary to defend anything concerning something that contradicts mainstream physics, you might quickly feel overwhelmed by the comments that people make who know what the are actually talking about.


I've read some of these threads. I agree that most in fact are nonsense, not even really worth bothering to entertain. Nevertheless the usual crowd will show up to participate in a good stoning. In these "stonings" at least some of the members who participate truly do not know what they are talking about, and cannot correctly demonstrate why something is wrong. They merely parrot the mainstream and insist that the poster is wrong. That puts these members somewhat in the same category as the electric sun poster in terms of knowledge of physics.

I respect the knowledge and education that some members like yourself reveal! I like to ask questions, but I often get evasive answers or answers so indirect as to be frustrating. Read my thread "How can we see the CMB". I made some incorrect assumptions used some math and came up with something incorrect. I asked someone to explain what was wrong with my reasoning, but it was like pulling teeth. Finally a kindly expert came along and just flat out told me what the problem was and I agreed. Then I asked about another part of my assumptions and why it was wrong also, but no one is interested in telling me. It's as if members are very interested in telling absolute novices, people with little understanding of physics and astronomy about the Universe according to the mainstream, but when the questioning gets more detailed, they become evasive in answers, tell you to go read lots of papers or just abandon the thread. Not nearly as generous as they are to the completely uneducated.



However, nobody is forcing you to stay here, there are many other boards where you may discuss this kind of stuff, but I must say that BAUT is one of the nicer ones, but take a look around at e.g. JREF or tommac's board.

That's absolutely true. I going to be inactive now, because it's not much fun when no one wants discuss possibilities but only insist on the finality of the status quo.

tusenfem, I've got to give you some points here for not blowing your top and just banning me.

I've been foaming at the mouth too long here. Sorry if I've offended many members, but you've offended me too.

One thing I think we can agree on is that astronomy today is exciting.

Cheers!

Shaula
2012-Jun-10, 07:41 AM
In this forum, members and administrators create a pretense that everything is settled; the theory is correct, period.
Just had to reply to this: no we don't We frequently and honestly admit that there are limits to our theories, that they are just theories and that they may well be superseded. I say it all the time, others do to. What we do say is that these other ideas have less evidence for them, that they fit the wider picture less well. And in some cases they are simply not consistent with observations. FYI, and I have said this before, I personally really do not like dark energy or some other aspects of cosmology. It grates against my sensibilities. My brain says no. But on reviewing the evidence and the models - I can think of or find nothing that fits better. So I go with it. That is what science is about and what the mainstream is based on. You clearly do not like the mainstream and so find any reason, any at all, to infer that it is wildly wrong. Without really doing the background reading required to assess what the evidence you quote is saying or how consistent it is.

Derail over. Just wanted to get that off my chest!

antoniseb
2012-Jun-10, 11:41 AM
... the impression it gives is rather like in faiths where the believers will condemn any information not consistent with their beliefs as incorrect or impossible. ...

This is a violation of our no religion policy, which you've previously violated (second violation).
The fact that you are posting in this thread at all after being forbidden to from previous moderation is a violation.
The fact that this post is not at all about the creation of new galaxies is also an issue.

You're likely to get a few points here, which means some time off in your case.
I'm informing you publicly, because we've received many alerts about your recent posts, and people are interested in knowing what we're doing here.