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The Bad Astronomer
2003-Jan-15, 11:44 PM
While reading a lengthy article about active galaxies and quasars (here, for those interested (http://www.astr.ua.edu/keel/agn/quasar40.html)), I had a thought I want to put here, for people more familiar with these topics than I am. It may provide further evidence that Arp and his followers are wrong, and provide strong evidence for an expanding Universe and the Big Bang.

When a spectrum is taken of a high-redshift quasar, it invariably shows a series of absorption lines blueward of the Lyman alpha line (this is the emission line of hydrogen where the electron drops from the 2nd to the 1st energy level, and has a wavelength of 1216 Angstroms).

The standard explanation is that there is gas between us and the quasar. This gas, being closer to the quasar, sees the quasar at a lower redshift. We might see the Lyman alpha line redshifted to, say, 2432 Angstroms (at a redshift of 1), but the gas sees it as a redshift of 0.5. The gas absorbs this light, leaving an absorption line in its spectrum at where it sees the quasar's Lyman alpha.

However, the gas is redshifted with respect to us too, but not as much as the quasar, so we see this absorption feature to the blue of the Lyman alpha line from the quasar.

If there are lots and lots of gas clouds between us and the quasar, we would see lots and lots of absorption lines; a "forest" of them, all blueward of the emission line from the quasar itself. This is what's called the Lyman alpha forest, and to the best of my knowledge appears in every single high-redshift quasar spectrum.

I see this as a major problem with Arp's interpretation of redshift being something internal to the quasar. In his book, "Seeing Red", he claims that quasars are ejected from galaxies, and their redshift changes as they age. It has little or nothing to do with distance. The redshift is happening due to "new physics" inside the quasar itself.

So how does he (or his followers) explain the Lyman alpha forest? The forest falls naturally out of a redshift/distance correlation, but not if the redshift is intrinsic. The gas all has to see the quasar at different redshifts, but this is not possible if the quasar itself is the source of its own redshift.

Is this the nail in the coffin of Arp's theory? I have not seen it discussed in this way elsewhere.

JS Princeton
2003-Jan-16, 12:03 AM
I agree, Phil, that such evidence seems damning. I've mentioned it before and received the comment that the intrinsic redshift might be related in some sort of potential to the outside. In other words, that the absorption features might not be intergalactic clouds at all but rather intrinsic to the quasar itself.

I find this preposterous because we see the same z-absorbers in quasars that are on similar lines of sight but with different redshifts. Why should the features in one intrinsic quasar be the same in another one only when they are on the same line of sight? I mean, the quasars are different (at different redshifts) and yet they show the same absorption features with the SAME OPTICAL DEPTHS! This is a ridiculous coincidence that the intrinsic redshifters have NEVER explained to me, even though I've mentioned it numerous times.

harlequin
2003-Jan-16, 01:06 AM
Hey I like that easy to understand (for a non-astronomer) explanation of why Arp is wrong. Though I never thought that his connections between near-by galaxies and quasars looked all that impressive. If anything I am surprised that he was not able to find more of them by chance alignments.

I do have a question. I can think of a way that could really put another nail in coffin of Arp's hypothesis. Take one of the galaxy/quasar pairs that Arp says are physically connected. If the quasar is really much further distant than that Galaxy and the appearent connection is just the result of a chance alignment between the quasar and the galaxy, then should it not be possible that quasar's light will be absorbed by gas from that galaxy? If the answer is yes, the observational consequence would be very obvious.

Tim Thompson
2003-Jan-16, 02:33 AM
The king of Bad Astronomers has made a point that is already enshrined in the inscrutable aether of the scientific literature.

Evidence consistent with the cosmological interpretation of quasar redshifts (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002PYunO..90...16L&db_key=AST&high=3cf96e067124623)
En-Wei Liang & Yi-Ping Qin
Publications of the Yunnan Observatory 90(2): 16-21 (2002)
Abstract: We select a sample including 401 sources in which both absorption and emission redshifts are available from the table 1 in Hewitt and Burbidge (1993). The sample is the largest one for the investigation of the quasar redshifts so far. It is found that most of the absorption redshifts (93.6%) are smaller than the corresponding emission redshifts, and the result is consistent with the conclusion drawn from a small sample in 1970s. The result indicates that the redshifts of quasars are indeed distance indicators. That is consistent with the cosmological interpretation of quasar redshifts.

The problem is the relative obscurity of the source. Not everybody has the Publications of the Yunnan Observatory laying around, and many of the abstract archives don't include it either. It's just my luck that I found the paper at the Caltech library (which does have the Publications of the Yunnan Observatory laying around in the astronomy department library). I saw the paper, but don't think I have a copy. They have a nice plot of all the quasar redshifts vs Lyman-alpha redshifts. It's a pretty impressive picture.

Along with the Lyman-alpha forest, one might include the logically connected Gunn-Peterson trough, caused by the absorption of neutral hydrogen in the universe, before the epoch of re-ionization (or so standard cosmology predicts). Long a theoretical expectation, the Gunn-Peterson trough is now an observed reality (VLT optical and near-infrared observations of the z=6.28 quasar SDSS J1030+0524, L. Pentericci et al., Astronomical Journal 123(5): 2151-2158, May 2002; A survey of z greater than 5.8 quasars in the Sloan Digital Sky Survey. I. Discovery of three new quasars and the spatial density of luminous quasars at z similar to 6, X.H. Fan et al., Astronomical Journal 122(6): 2833-2849, December 2001; Evidence for reionization at z similar to 6: Detection of a Gunn-Peterson trough in a z=6.28 quasar, R.H. Becker et al., Astronomical Journal 122(6): 2850-2857, December 2001).

I like to think that the combo of Lyman-Alpha forest & Gunn-Peterson trough are like a one-two punch that needs to be dealt with by anyone who thinks redshifts of quasars are non-cosmological.

harlequin ... If the quasar is really much further distant than that Galaxy and the appearent connection is just the result of a chance alignment between the quasar and the galaxy, then should it not be possible that quasar's light will be absorbed by gas from that galaxy? If the answer is yes, the observational consequence would be very obvious.

There are published papers which show just that. The galaxy absorbs quasar light, showing that the quasar lies in the background. Not all of the suspicious galaxy-quasar pairs show this, but at least some can be discounted for the reason you cite (examples, New observations of the gas cloud associated with the quasar-galaxy pair 3C-232 NGC-3067, J.T. Stocke et al., Astrophysical Journal 374(1): 72-82, Part 1, June 10 1991; Properties of low redshift QSO absorption systems - QSO-galaxy pairs, D.S. Womble, Publications of the Astronomical Society of the Pacific 105(691): 1043-1050, September 1993). I have posted other examples in other threads, but unfortunately I am not so well organized as to have them handy.

I hope I didn't misspell shift again.

Cheers.

The Bad Astronomer
2003-Jan-16, 04:45 AM
Tim, you're the Man. /phpBB/images/smiles/icon_smile.gif

I'll note that there is a description of the Gunn-Peterson effect in the paper I linked in my original post to this thread.

It's nice to know I can be backed up with science.

AgoraBasta
2003-Jan-16, 04:01 PM
Please don't y'all consider me as a believer in close quasars or Arp/Narlikar's "new physics" (which I hate yet deeper than the Big Bang itself), but why don't you consider a hydrogen atmosphere around the quasar itself? The thing might be very heavy to produce local redshifts, yet charged too much to collapse. Anybody ever modelled that?

Zathras
2003-Jan-16, 04:20 PM
On 2003-01-16 11:01, AgoraBasta wrote:
Please don't y'all consider me as a believer in close quasars or Arp/Narlikar's "new physics" (which I hate yet deeper than the Big Bang itself), but why don't you consider a hydrogen atmosphere around the quasar itself? The thing might be very heavy to produce local redshifts, yet charged too much to collapse. Anybody ever modelled that?


I would think that an atmosphere at best would cause a broadening of the line, because the redshift would be continuous, rather than the discrete lines that make up the Lyman alpha forest.

<font size=-1>[ This Message was edited by: Zathras on 2003-01-16 11:24 ]</font>

AgoraBasta
2003-Jan-16, 04:43 PM
On 2003-01-16 11:20, Zathras wrote:
I would think that an atmosphere at best would cause a broadening of the line, because the redshift would be continuous, rather than the discrete lines that make up the Lyman alpha forest.That must depend on the density. After all, that light gets that much hydrogen anyway...

But my question was were there any attempts of the nature I mentioned, or any serious consideration for "intrinsicness" at all (I mean - no overly new physics).

harlequin
2003-Jan-16, 07:20 PM
On 2003-01-16 11:01, AgoraBasta wrote:
Please don't y'all consider me as a believer in close quasars or Arp/Narlikar's "new physics" (which I hate yet deeper than the Big Bang itself), but why don't you consider a hydrogen atmosphere around the quasar itself? The thing might be very heavy to produce local redshifts, yet charged too much to collapse. Anybody ever modeled that?


This is a perfect example of desperate hand waving that quacks will go though to get around the evidence. How could an "atmosphere" of a quasar have a redshift that is both different and distinct from the quasar itself?

[Edited to improve clarity and grammar.]


<font size=-1>[ This Message was edited by: harlequin on 2003-01-16 14:57 ]</font>

JS Princeton
2003-Jan-16, 07:24 PM
On 2003-01-16 11:01, AgoraBasta wrote:
Please don't y'all consider me as a believer in close quasars or Arp/Narlikar's "new physics" (which I hate yet deeper than the Big Bang itself), but why don't you consider a hydrogen atmosphere around the quasar itself? The thing might be very heavy to produce local redshifts, yet charged too much to collapse. Anybody ever modelled that?


Agora, but two different quasars on similar lines of sight show convergeant signals from z-absorbers at EXACTLY where we see, for example, the Virgo cluster. How could those signals be part of the quasar atmosphere?

AgoraBasta
2003-Jan-16, 07:28 PM
On 2003-01-16 14:20, harlequin wrote:
This is a perfect example of desperate hand waving quacks will go to get around the evidence.Come on, you can't possibly be that intellectually crippled yet still able to write a post...

harlequin
2003-Jan-16, 07:46 PM
Tim,

Thanks for confirming my hunch.

Bad Astronomer (or Tim),

This would a great subject for a page. This is something that be easily explained to people without a technical astronomy background.


===================

There is another posible way to use this sort of argument. Maybe Tim or J S Princton (whose post influenced this) can say if it has been done. Say there are two quasars that whose position to each other two-dimentionally (i.e. not counting distance) is fairly small. There are far enough from the line of sight for Arp not to claim they are "connected" but close enough to the line of sight to have there light absorbed by the same "cloud" of hydrogen. They will get some lines in their spectrum from it. Princeton said this has been done in his reply to The Bad Astronomer. But the farther one can also get absorption from
hydrogen that is even further out that the
other quasar does not have. Has that been observed?

If someone can show some examples of this, then I say that we can say with about as close to absolute confidence as one get in the real world that non-mainsteam explanations of the red shifts are false.

AgoraBasta
2003-Jan-16, 07:49 PM
On 2003-01-16 14:24, JS Princeton wrote:
Agora, but two different quasars on similar lines of sight show convergeant signals from z-absorbers at EXACTLY where we see, for example, the Virgo cluster. How could those signals be part of the quasar atmosphere?That would be a coincidence for Arp to match! /phpBB/images/smiles/icon_smile.gif Yet I'd ask a few questions -
Are there parts in their absorption spectra that don't match, yet come from atomic hydrogen; what's the weight of convergent parts?
Do the "closest" quasars exhibit appropriately less forest effect?

<font size=-1>[ This Message was edited by: AgoraBasta on 2003-01-16 14:54 ]</font>

GrapesOfWrath
2003-Jan-16, 08:05 PM
On 2003-01-16 14:20, harlequin wrote:
This is a perfect example of desperate hand waving that qua*ks will go though to get around the evidence.
No ducks here.

Aldrin
2003-Jan-16, 08:13 PM
Latest discovery from Hubble.
For years, double cosmic clouds of radio emission such as those flanking this spiral galaxy's core have been studied and cataloged. But, at least until now, such radio sources were only known to arise from the cores of giant elliptical galaxies or in violent merging galaxy systems, making 0313-192 the wrong kind of galaxy to be found in this scenario. Astronomers are searching for clues to why this spiral galaxy, potentially similar to our own Milky Way, shows such powerful activity.

http://antwrp.gsfc.nasa.gov/apod/ap030114.html

JS Princeton
2003-Jan-16, 09:12 PM
On 2003-01-16 14:49, AgoraBasta wrote:

On 2003-01-16 14:24, JS Princeton wrote:
Agora, but two different quasars on similar lines of sight show convergeant signals from z-absorbers at EXACTLY where we see, for example, the Virgo cluster. How could those signals be part of the quasar atmosphere?That would be a coincidence for Arp to match! /phpBB/images/smiles/icon_smile.gif Yet I'd ask a few questions -
Are there parts in their absorption spectra that don't match, yet come from atomic hydrogen; what's the weight of convergent parts?
Do the "closest" quasars exhibit appropriately less forest effect?

<font size=-1>[ This Message was edited by: AgoraBasta on 2003-01-16 14:54 ]</font>


The only parts that don't match are the parts from redshifts that are larger in one than the redshift of the other object.

There definitely are fewer absorption features in quasars that have lower redshifts.

AgoraBasta
2003-Jan-16, 09:47 PM
On 2003-01-16 16:12, JS Princeton wrote:
The only parts that don't match are the parts from redshifts that are larger in one than the redshift of the other object.

There definitely are fewer absorption features in quasars that have lower redshifts.Thus hydrogen atmospheres won't help them... I have no doubt they'll find some fun elsewhere. /phpBB/images/smiles/icon_wink.gif

Spaceman Spiff
2003-Jan-17, 04:02 AM
On 2003-01-15 20:06, harlequin wrote:
Hey I like that easy to understand (for a non-astronomer) explanation of why Arp is wrong. Though I never thought that his connections between near-by galaxies and quasars looked all that impressive. If anything I am surprised that he was not able to find more of them by chance alignments.

I do have a question. I can think of a way that could really put another nail in coffin of Arp's hypothesis. Take one of the galaxy/quasar pairs that Arp says are physically connected. If the quasar is really much further distant than that Galaxy and the appearent connection is just the result of a chance alignment between the quasar and the galaxy, then should it not be possible that quasar's light will be absorbed by gas from that galaxy? If the answer is yes, the observational consequence would be very obvious.



In addition to the ones that Tim mentioned, there's also the case of the most famous of the so-called alignment systems involving the quasar Mrk 205. The quasar's spectrum shows narrow MgII absorption lines at the redshift of the foreground galaxy (with the so-called 'bridge').
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1993ApJ...403L..55B&db_key=AST&high=3e2780004c02697

But besides these Arpian cases, there must be many dozens (hundreds?) of known cases of quasar absorption line systems observed along lines of sights that lie near or through the disks and halos of spiral galaxies (Lyman limit and damped Lyman alpha systems). (Papers by Ken Lanzetta, Chuck Steidel, many others)

As for the gas that lies between galaxy clusters responsible for the vast majority of the low column density absorption lines, simulations of the formation of large scale structure in an expanding universe can actually reproduce the Lyman alpha forest and its evolution with redshift (it thins out at low redshift -- just a dozen or so lines in the spectrum of 3C 273 and other "nearby" quasars, and the forest becomes totally opaque for wavelengths shortward of the Lyman alpha emission line by the highest redshift quasars z > 6). (numerical modeling papers by Neil Katz and David Weinberg, others)



<font size=-1>[ This Message was edited by: Spaceman Spiff on 2003-01-16 23:09 ]</font>

D J
2003-Jan-17, 10:10 PM
On 2003-01-15 18:44, The Bad Astronomer
If there are lots and lots of gas clouds between us and the quasar, we would see lots and lots of absorption lines; a "forest" of them, all blueward of the emission line from the quasar itself. This is what's called the Lyman alpha forest, *and to the best of my knowledge appears in every single high-redshift quasar spectrum.*

I dont arguing against what you said,but the fact than the Lyman alpha forest appears ONLY in every single high-redshift quasar spectrum and is not visible in lower Redshift quasars imply a limited aera (zone)of gas clouds centered around high redshift quasars or the Layman alpha forest should be visible on all redshift of Quasars not only the high redshift.Because we would see the absorption lines each time the light of the Quasar -even with a lower redshift- travel through a gas cloud betwen us. This should be visible in the spectrum line for all quasars observed?

<font size=-1>[ This Message was edited by: Orion38 on 2003-01-17 17:40 ]</font>

JS Princeton
2003-Jan-17, 10:50 PM
Orion, there are two effects: one: there are fewer clouds of absorbable material to go through for lower redshift quasars. Two, the way redshift works, especially high redshift, you end up with "length contraction" effects. That's why it's a forest, because even though you've gone way, way out, you have a finite amount of wavelength space in which to absorb all the way back to z=0. This means that most of your absorbers tend to cluster up in the higher-redshifts (thus looking like a forest).

Low redshift, the formula reduces to v=zc and so you needn't worry about running out of wavelengths to absorb back down to rest-frame Ly-alpha.

Dunash
2003-Jan-17, 11:32 PM
Arp has his own forums. Have any of you posted there your doubts & received responses from him or his devotees?

http://www.haltonarp.com/?Page=Forum

John Kierein
2003-Jan-19, 03:29 PM
The forest and the trough is easily explained by an intrinsic red shift with a Compton effect interpretion of the red shift. In this mechanism, the red shift occurs from interactions of the light from the source with intervening electrons. These electrons are actually seen in some of these sources with large magnetic fields from their synchrotron radiation. There can be layers of un-ionized hydrogen intrinsic to the source between the observer and the source to produce these. The trough should be seen especially in an atmosphere of electrons without a magnetic field (No synchroton radiation for these sources)due to the outer portions of the atmosphere cooling and the electrons and protons combining to form hydrogen. This hydrogen would be seen at a lesser red shift.
Models of quasars with multiple red shifts are somewhat hard to build from cosmological models, since the differing red shifts corespond to many millions of light year differences in distance. They are not quite so hard with intrinsic models. The intrinsic models can have the differing shifts from local rings or spheres of material at the quasar vicinity.

The cosmological interpretation of the Lyman alpha forest implies that the light is interacting with intervening material, mainly hydrogen. But it is never considered that the light could be interacting with ionized hydrogen which is free electrons and protons. You would see no spectral lines from such an interaction, but you should see a red shift from the Compton effect.

The Lyman Alpha forest should be seen in high redshift galaxies. Is it the same as quasars of comparable red shift?

<font size=-1>[ This Message was edited by: John Kierein on 2003-01-19 10:52 ]</font>

traztx
2003-Jan-19, 05:45 PM
On 2003-01-19 10:29, John Kierein wrote:
The Lyman Alpha forest should be seen in high redshift galaxies. Is it the same as quasars of comparable red shift?


I'm curious about that too. I wonder if galaxies are too diffuse to allow a good measurement.

The Bad Astronomer
2003-Jan-19, 07:20 PM
On 2003-01-17 18:32, Dunash wrote:
Arp has his own forums. Have any of you posted there your doubts & received responses from him or his devotees?

http://www.haltonarp.com/?Page=Forum


I went there, but the posts are unthreaded, and I cannot make heads or tails of what people are talking about! I have seen several BBs like that, and I wonder why people don't use better software (this board, for example, is free). Anyway, I would rather not post there simply because of this; otherwise I'd be curious to see the answer (honestly; I read several BBs and it gets tiresome very quickly spending more time trying to understand the context rather than the content). If someone else wants to post there, feel free.

Chip
2003-Jan-19, 07:23 PM
Though short lived, would not the redshifts of Gamma-Ray Bursts also display similar Lyman alpha forest absorption effects from hydrogen clouds? (Being as Gamma-Ray Bursts are also very bright and very far away.)

The Bad Astronomer
2003-Jan-19, 09:39 PM
On 2003-01-19 14:23, Chip wrote:
Though short lived, would not the redshifts of Gamma-Ray Bursts also display similar Lyman alpha forest absorption effects from hydrogen clouds?

I suppose they would. The problem is that you need to get a deep spectrum to see them, and in general they fade so quickly that only getting an image is possible (a spectrum spreads the light out over many pixels, so you need lots more exposure time in general than an image). Also, you need a detector sensitive in the blue to get a good spectrum in the right region, unless the GRB is at a very high redshift. At a z=2, the Lyman alpha line is at 3648 Angstroms, still a bit in the blue of the optical. At UV wavelengths, you need a 'scope out in space.

However, a follow-up spectrum is an interesting proposal. I do some work with GRB follow-up, so I'll have to think about this.

Spaceman Spiff
2003-Jan-20, 01:05 AM
On 2003-01-19 12:45, traztx wrote:


On 2003-01-19 10:29, John Kierein wrote:
The Lyman Alpha forest should be seen in high redshift galaxies. Is it the same as quasars of comparable red shift?


I'm curious about that too. I wonder if galaxies are too diffuse to allow a good measurement.


To see the Lyman alpha forest, the intrinsic spectrum of the obscured object must extend to wavelengths shortward of Lyman alpha (1216 Angstroms). Most galaxies don't have a lot of energetic UV light extending down to THOSE wavelengths, though perhaps those going through a WHOPPING starburst might. I don't have a reference for such a case. Anybody else?

Spaceman Spiff
2003-Jan-20, 01:09 AM
On 2003-01-19 16:39, The Bad Astronomer wrote:


On 2003-01-19 14:23, Chip wrote:
Though short lived, would not the redshifts of Gamma-Ray Bursts also display similar Lyman alpha forest absorption effects from hydrogen clouds?

I suppose they would. The problem is that you need to get a deep spectrum to see them, and in general they fade so quickly that only getting an image is possible (a spectrum spreads the light out over many pixels, so you need lots more exposure time in general than an image). Also, you need a detector sensitive in the blue to get a good spectrum in the right region, unless the GRB is at a very high redshift. At a z=2, the Lyman alpha line is at 3648 Angstroms, still a bit in the blue of the optical. At UV wavelengths, you need a 'scope out in space.

However, a follow-up spectrum is an interesting proposal. I do some work with GRB follow-up, so I'll have to think about this.


BA, haven't we estimated lower limits of the redshifts of GRBs through absorption lines within in their fireball spectra due to IGM lying along the line of sight?

Spaceman Spiff
2003-Jan-20, 01:44 AM
On 2003-01-19 10:29, John Kierein wrote:
The forest and the trough is easily explained by an intrinsic red shift with a Compton effect interpretion of the red shift. In this mechanism, the red shift occurs from interactions of the light from the source with intervening electrons. These electrons are actually seen in some of these sources with large magnetic fields from their synchrotron radiation. There can be layers of un-ionized hydrogen intrinsic to the source between the observer and the source to produce these. The trough should be seen especially in an atmosphere of electrons without a magnetic field (No synchroton radiation for these sources)due to the outer portions of the atmosphere cooling and the electrons and protons combining to form hydrogen. This hydrogen would be seen at a lesser red shift.


This is just hand waving. First, what is your mechanism for making multiple absorption lines? Next, your electron plasma does not produce the observed redshifts. In fact, from your previous posts you claim such a plasma would be relativistic. A relativistic gas' particles have more energy than the photons in question, and as such would cause very small BLUEshifts via inverse Compton scattering.

Besides the fact that your "theory" has never been demonstrated to have any basis in known natural laws, it suffers from the following: somehow your magic plasma doesn't do anything but cause redshifts in the spectra of quasars. It doesn't smear out (to any measureable degree) the light passing through it, at ANY wavelength. If it did, we'd measure that. In fact there are some radio bright Quasars and elliptical galaxies that emit strongly at radio waves with lots of very hot gas surrounding them (we see it at x-ray wavelengths). No scintellation of the nuclear radio source of any consequence is observed. Your magic medium doesn't emit any light (that's a real good one) - or we'd see it (and as I said, we do see hot plasma surrounding galaxies, but with properties consistent with known physical laws and with small optical depths to Compton scattering causing VERY TINY shifts in photon wavelengths). It never causes blue shifts, when such a hot plasma (as you've described it) sure should via inverse Compton scattering. There is enough of your magic medium to cause enormous spectral shifts, yet not so much that the medium is opaque or in fact has any measurable properties other than the one you set out to assign it to - quasar redshifts. It's magic, and it's all in your head.



Models of quasars with multiple red shifts are somewhat hard to build from cosmological models, since the differing red shifts corespond to many millions of light year differences in distance. They are not quite so hard with intrinsic models. The intrinsic models can have the differing shifts from local rings or spheres of material at the quasar vicinity.


There is no such problem of differing sets of redshifts (as you point them out here), except in your mind. Those that are known are understood as intrinsic Doppler effects due to intrinsic dynamical motions of gas within the quasar - the kinds of motion in the local vicinity of a supermassive black hole.



The cosmological interpretation of the Lyman alpha forest implies that the light is interacting with intervening material, mainly hydrogen. But it is never considered that the light could be interacting with ionized hydrogen which is free electrons and protons. You would see no spectral lines from such an interaction, but you should see a red shift from the Compton effect.


And so the observed absorption lines are due to? We see Lyman series (alpha, beta, gamma, etc) at the same redshifts. Often, too, at the same redshifts we see absorption lines from ionized heavy elements (carbon, silicon, iron, etc). Often at the same redshifts we see galaxies or galactic halos - with the very gas causing the absorption we see in quasar spectra.

D J
2003-Jan-20, 01:51 AM
On 2003-01-19 20:09, Spaceman Spiff wrote:
[quote]
BA, haven't we estimated lower limits of the redshifts of GRBs through absorption lines within in their fireball spectra due to IGM lying along the line of sight?



I ran accross this:
http://lithops.as.arizona.edu/~jill/A515.ref/rauch267.pdf

Recent progress with cosmological hydro-simulations based on hierarchical

structure formation models has led to important insights into the physical struc-

tures giving rise to the forest. *If these ideas are correct, a truly inter- and pro-

togalactic medium at high redshift Z 3*

the main repository of baryons
collapses under the influence of dark matter gravity into flattened or filamentary
structures, which are seen in absorption against background QSOs. With decreas-
ing redshift, galaxies forming in the denser regions may contribute an increasing
part of the Ly
absorption cross section.
More details:

Link to more details (http://216.239.33.100/search?q=cache:bbhMKyhMVKMC:lithops.as.arizona.edu/~jill/A515.ref/rauch267.pdf+the+Lyman+Alpha+Forest+alternative+ex planation&hl=en&ie=UTF-8) (link edited by The Bad Astronomer for formatting reasons)

<font size=-1>[ This Message was edited by: Orion38 on 2003-01-19 20:53 ]</font>

<font size=-1>[ This Message was edited by: Orion38 on 2003-01-19 20:57 ]</font>

<font size=-1>[ This Message was edited by: Orion38 on 2003-01-20 01:07 ]</font>

<font size=-1>[ This Message was edited by: The Bad Astronomer on 2003-01-26 14:57 ]</font>

John Kierein
2003-Jan-20, 08:26 PM
Spiff: The redshifts do not necessarily produce a relativistic plasma, (see e.g., the solar redshift and the center to limb variation) but sometimes we DO get synchroton radiation, and superluminal jets. The multiple redshifts seen in quasar spectra may be due to rings or shells of material around the quasar. Most of them are at low temperatures consistent with stellar spectra. (i.e., temperatures less than 10,000K) The ions can be intermingled like in this candle flame:
http://www.americanantigravity.com/flametest.html

<font size=-1>[ This Message was edited by: John Kierein on 2003-01-20 16:17 ]</font>

Spaceman Spiff
2003-Jan-21, 02:31 PM
On 2003-01-20 15:26, John Kierein wrote:
Spiff: The redshifts do not necessarily produce a relativistic plasma, (see e.g., the solar redshift and the center to limb variation) but sometimes we DO get synchroton radiation, and superluminal jets. The multiple redshifts seen in quasar spectra may be due to rings or shells of material around the quasar. Most of them are at low temperatures consistent with stellar spectra. (i.e., temperatures less than 10,000K) The ions can be intermingled like in this candle flame:
http://www.americanantigravity.com/flametest.html

<font size=-1>[ This Message was edited by: John Kierein on 2003-01-20 16:17 ]</font>


Ok, fine -- except that you still have no physical mechanism. I was just quoting from your many past (and recent) posts on the subject.

But now you bring up another of your favorite unsubstantiated statements about quasars -- that their spectra are consistent with stars. This is completely untrue. Neither their continua or their emission lines are in any way star-like.



<font size=-1>[ This Message was edited by: Spaceman Spiff on 2003-01-21 09:32 ]</font>

JS Princeton
2003-Jan-21, 03:57 PM
Stars and quasars look completely different in terms of their spectra. Completely. There really is no comparison that can be made other than looking at the microphysics of emmission and absorption. The underlying continua look NOTHING like each other.

Chip
2003-Jan-23, 12:27 AM
BA wrote:
"...Also, you need a detector sensitive in the blue to get a good spectrum in the right region, unless the GRB is at a very high redshift. At a z=2, the Lyman alpha line is at 3648 Angstroms, still a bit in the blue of the optical. At UV wavelengths, you need a 'scope out in space..."

Spaceman Spiff wrote:
"To see the Lyman alpha forest, the intrinsic spectrum of the obscured object must extend to wavelengths shortward of Lyman alpha (1216 Angstroms). Most galaxies don't have a lot of energetic UV light extending down to THOSE wavelengths, though perhaps those going through a WHOPPING starburst might."

Chip asks:
Is this purely a matter of engineering, or is it the nature of the light itself? (I'm naive in the area of modern, sophisticated spectrographic equipment/programming designs.) In other words, could a detector be built that allows for a useful spectrum at UV wavelengths for short lived, yet very bright GRB events?

Does Northwestern University's new gallium nitride detector (http://oemagazine.com/newscast/031802_newscast01.html) apply to this? I get the impression from this press release that it is eventually destined to go in the Hubble Space Telescope. /phpBB/images/smiles/icon_wink.gif

<font size=-1>[ This Message was edited by: Chip on 2003-01-22 19:29 ]</font>

Spaceman Spiff
2003-Jan-23, 05:29 AM
On 2003-01-22 19:27, Chip wrote:
BA wrote:
"...Also, you need a detector sensitive in the blue to get a good spectrum in the right region, unless the GRB is at a very high redshift. At a z=2, the Lyman alpha line is at 3648 Angstroms, still a bit in the blue of the optical. At UV wavelengths, you need a 'scope out in space..."

Spaceman Spiff wrote:
"To see the Lyman alpha forest, the intrinsic spectrum of the obscured object must extend to wavelengths shortward of Lyman alpha (1216 Angstroms). Most galaxies don't have a lot of energetic UV light extending down to THOSE wavelengths, though perhaps those going through a WHOPPING starburst might."

Chip asks:
Is this purely a matter of engineering, or is it the nature of the light itself? (I'm naive in the area of modern, sophisticated spectrographic equipment/programming designs.) In other words, could a detector be built that allows for a useful spectrum at UV wavelengths for short lived, yet very bright GRB events?

Does Northwestern University's new gallium nitride detector (http://oemagazine.com/newscast/031802_newscast01.html) apply to this? I get the impression from this press release that it is eventually destined to go in the Hubble Space Telescope. /phpBB/images/smiles/icon_wink.gif

<font size=-1>[ This Message was edited by: Chip on 2003-01-22 19:29 ]</font>


If the spectrum of the galaxy is to show enough UV light to see a significant Lyman alpha forest, it's gotta have a lot of hot stars, and I do mean a lot. There are such galaxies (sort of) and they are called Lyman break galaxies, seen often at high redshift. The problem here is that neutral hydrogen in the vicinity of the galaxy (probably the forming galaxy itself) is thick enough to absorb all UV light shortward of 912 Angstroms (ionization limit of Hydrogen). In fact the Lyman line series is so opaque that the spectrum begins cutting off even a bit above this. Thus the name - "Lyman break galaxy" - a break in the spectrum (to zero flux). Off hand I don't know of a reference to galaxies at high redshift that have sufficient UV light so that we can see the Lyman alpha forest, originating in the intergalactic medium.

Quasars produce energetic light from infrared all the way through the X-rays in enormous quantities, so seeing the forest is no problem using them as background light sources lighting up the intervening intergalactic medium.

The Bad Astronomer
2003-Jan-23, 06:03 AM
Just to make this clearer (or perhaps to confuse things), quasars are really just galaxies with active supermassive black holes in them. Spiff means normal galaxies, which glow only due to starlight and nebulae. The black hole in a quasar can produce EM radiation right up into gamma rays, so photons with higher energy than UV isn't a problem. Galaxies like the Milky Way aren't bright enough in those energies to see at great distances, so we don't see the Lyman break.

So at large distances, to see the Lyman forest, we need something that produces copious amounts of UV or higher energy photons. As far as we know, that means quasars and GRBs.

Chip
2003-Jan-23, 07:03 AM
BA & Spiff:
Hey thanks. This is all very interesting. I realize the gist of the thread is about quasars, but mentioned GRBs because they are so bright. They're extremely wild (and frankly creepy) events to me, (glad they're so far away in the past.)

Looking over this thread, I get the intuitive impression that if technology were developed that could capture a deep spectrum at UV wavelengths for short lived GRBs, then that might offer a secondary complimentary test to quasar spectrums. But there are sizeable gaps in my knowledge of both GRBs and Quasars, and I may be missing a lot and be wrong about that.
Chip

Spaceman Spiff
2003-Jan-23, 08:26 PM
On 2003-01-23 01:03, The Bad Astronomer wrote:
Just to make this clearer (or perhaps to confuse things), quasars are really just galaxies with active supermassive black holes in them. Spiff means normal galaxies, which glow only due to starlight and nebulae. The black hole in a quasar can produce EM radiation right up into gamma rays, so photons with higher energy than UV isn't a problem. Galaxies like the Milky Way aren't bright enough in those energies to see at great distances, so we don't see the Lyman break.

So at large distances, to see the Lyman forest, we need something that produces copious amounts of UV or higher energy photons. As far as we know, that means quasars and GRBs.


Yes, thanks, BA, for filling in some of the gaps I left.

John Kierein
2003-Jan-26, 03:22 PM
Today's APOD (1-26-03) discusses the forest. If you stand back and think about this, the current view is very scrambled. Big bangers think the cosmological principle is violated and that there are (or were) a lot more and varied hydrogen clouds at large distances than nearby. (The cosmological principal says that the large scale universe is pretty much the same everywhere and operates under our physics.)
But an intrinsic quasar red shift caused by the Compton effect for a small source inside a co-located plasma of free electrons and protons that can combine to form spheres or clouds of hydrogen answers the forest observations. That's why the forests only are seen in quasars and not in galactic sources of the same red shift. Despite the claims to the contrary, the forest is better evidence for intrinsic quasar red shifts than against it. Thus BA's claim that quasars are galaxies is very misleading and just not consistent with their intrinsic small size and variability. An intrinsic red shift interpretation of the forest is consistent with the cosmological principle.
Big bangers want to violate the cosmological principal with lots of theoretical what-ifs that have never been seen. Like a background temperature of the universe that was much higher in the past, a denser universe in the past, an inflationary period. None of these have ever been seen. In my view the CMBR has always been 3K, the galaxies have always looked like nearby ones, the number of galaxies per volume has always been the same, there was no inflationary period, the laws of physics are the same everywhere and the cosmological principal holds. The big bangers violate all these. They say the temperature was higher in the past, they first said galaxies evolve until they discovered that there are spirals at the greatest red shift, they say that there were more hydrogen filaments at large distances, they say the galaxies should be closer together at great distances without any evidence to support this, they say the laws of physics don't hold for the initiation of the big bang and that there is no such thing as before the big bang, they say that there was an inflationary period for which there is no evidence. Despite the fact that all cosmological theory was based on a cosmological principal to save the reasonableness of the models, they violate it left and right. As Grote Reber's paper says, "The Big bang is Bunk", the universe is an "Endless, Boundless, Stable Universe" that preserves the cosmological principle.

Quasars are much better explained if their red shift is intrinsic and they are not at the cosmolical rdistances of their red shift. Their jets do not have to be so large and fast as to be relativistic. Their brightness can be explained by their closeness. Their TEMPERATURE can be stellar since their spectra contains partially ionized elements that can only exist at stellar temperatures. (Despite what JS claims, I only said their spectra was stellar TEMPERATURE.) Their spectra can be similar at all red shifts without evolving as big bangers expect to violate the cosmological principal.

<font size=-1>[ This Message was edited by: John Kierein on 2003-01-26 10:42 ]</font>

<font size=-1>[ This Message was edited by: John Kierein on 2003-01-26 11:57 ]</font>

JS Princeton
2003-Jan-26, 06:45 PM
Welcome to the world of half-truths, by Big Bang deniers. Let's begin.



On 2003-01-26 10:22, John Kierein wrote:
Big bangers think the cosmological principle is violated and that there are (or were) a lot more and varied hydrogen clouds at large distances than nearby.

The fact of the matter is that reionization did not occur uniformly because the universe was out of causal contact. This means that pockets had to form. What's so hard to understand about that? The local structure and anisotropy of the universe is perfectly reasonable with regards to the cosmological principle, likewise local hydrogen clouds are acceptable too. In fact, reionization requires local processes to do the reionization. This means that you expect inhomogeneity on the local level.

All one has to do is read a few review papers on the subject to see why the Big Bang model predicts an inhomogeneous lyman-alpha forest. I recommend the following:



Title: The Local Ly&alpha; Forest. III. Relationship between Ly&alpha; Absorbers and Galaxies, Voids, and Superclusters
Authors: Penton, Steven V.; Stocke, John T.; Shull, J. Michael
Affiliation: AA(Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309; spenton@casa.colorado.edu, stocke@casa.colorado.edu, mshull@casa.colorado.edu), AB(Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309; spenton@casa.colorado.edu, stocke@casa.colorado.edu, mshull@casa.colorado.edu), AC(Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309; spenton@casa.colorado.edu, stocke@casa.colorado.edu, mshull@casa.colorado.edu)
Journal: The Astrophysical Journal, Volume 565, Issue 2, pp. 720-742. (ApJ Homepage)
Publication Date: 02/2002
Abstract

In this paper we use large-angle, nearby galaxy redshift surveys to investigate the relationship between the 81 low-redshift
Ly&alpha; absorbers in our Hubble Space Telescope GHRS survey and galaxies, superclusters, and voids. In a subsample of
46 Ly&alpha; absorbers located in regions where the 2000 February 8 CfA catalog is complete down to at least L* galaxies,
the nearest galaxy neighbors range from 100 h-170 kpc to greater than 10 h-170 Mpc. Of these 46 absorbers, eight are found in
galaxy voids. After correcting for path length and sensitivity, we find that 22%+/-8% of the Ly&alpha; absorbers lie in voids,
which requires that at least some low column density absorbers are not extended halos of individual bright galaxies. The number
density of these clouds yields a baryon fraction of 4.5%+/-1.5% in voids. The stronger Ly&alpha; absorbers (1013.2-1015.4
cm-2) cluster with galaxies more weakly than galaxies cluster with each other, while the weaker absorbers (1012.4-1013.2 cm-2)
are more randomly distributed. The median distance from a low-z Ly&alpha; absorber in our sample to its nearest galaxy
neighbor (~500 h-170 kpc) is twice the median distance between bright galaxies in the same survey volume. This makes any
purported ``association'' between these Ly&alpha; absorbers and individual galaxies problematic. The suggested correlation
between Ly&alpha; absorber equivalent width (&Wscr;) and nearest galaxy impact parameter does not extend to
&Wscr;<=200 mÅ or to impact parameters greater than 200 h-170 kpc. Instead, we find statistical support for the contention
that absorbers align with large-scale filaments of galaxies. The pair of sight lines, 3C 273 and Q1230+0115, separated by 0.9d
on the sky, provides an example of eight absorbers and seven galaxies aligned along a possible filamentary structure at least 20
h-170 Mpc long. While some strong (&Wscr;>400 mÅ) Ly&alpha; absorbers may be gas in the extended gaseous halos of
individual galaxies, much of the local Ly&alpha; ``forest'' appears to be associated with the large-scale structures of galaxies
and some with voids. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope
Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract
NAS 5-26555.

There is nothing spotty at all about this if you realize that the reionization regions are all local while recombination occurred across the horizon.


(The cosmological principal says that the large scale universe is pretty much the same everywhere and operates under our physics.)

Indeed it does, and that's why a local effect like the Lyman-alpha forest doesn't violate it.



But an intrinsic quasar red shift caused by the Compton effect for a small source inside a co-located plasma of free electrons and protons that can combine to form spheres or clouds of hydrogen answers the forest observations.

No better than a reionization scenario. Really, JK, you expect us to believe that this hasn't been thought about?


That's why the forests only are seen in quasars and not in galactic sources of the same red shift.

The explanation for the lyman-alpha forest relies heavily upon two things: asymmetry in coherent lines of sight and smaller than galactic sizes for the clouds. These two necessities from structure simulations ensure that the quasars as point-like as opposed to extended source objects will see the lyman-alpha forest. For more on this, see the tutorial: http://astron.berkeley.edu/~jcohn/lya.html


The forest is better evidence for intrinsic quasar red shifts than against it. No, because we have no physical mechanism for producing a differentiated plasma in local quasars as JK proposes. Think about it, why should the lyman-alpha system associated with a local quasar be at discrete and non-symmetric intervals unobservable by any other means? It has no basis in anything physical whatsover.


Thus BA's claim that quasars are galaxies is very misleading and just not consistent with their intrinsic small size and variability.

No, we have seen the galaxies around quasars now. At least in those instances even Arp must admit that those quasars are the "real deal".



Big bangers want to violate the cosmological principal with lots of theoretical what-ifs that have never been seen. Like a background temperature of the universe that was much higher in the past,

Well observed using the Sunyaev-Zeldovich effect and X-ray studies of cluster gas. I will show you the appropriate papers if you're interested, JK, but the results are that temperatures have been measured for the background at different redshifts and the universe WAS hotter then.


a denser universe in the past,

Also observed in deep surveys and in activity profiles that allow for such things as AGN and quasars.



an inflationary period.

Theoretically robust, though difficult to understand. This one doesn't have observational evidence for it except for anisotropies in the CMB which are well explained by it but are totally ignored by Big Bang deniers. Sour grapes, I guess.


In my view the CMBR has always been 3K, the galaxies have always looked like nearby ones, the number of galaxies per volume has always been the same, there was no inflationary period, the laws of physics are the same everywhere and the cosmological principal holds.

Well, we know that view number one has been disproven by observational evidence. We also know that view number two is up to interpretation. Comoving volume definitely has you (but you don't believe in it, methinks). The laws of physics being the same everywhere at all times is also held by Big Bangers, JK.


The big bangers violate all these.

This is a blatant and sorry lie. I wish you would stick to the facts, but it seems as though you are unable. It is very similar to your insistence that a difference in velocities could not cause a redshift... it's just not true.


They say the temperature was higher in the past, they first said galaxies evolve until they discovered that there are spirals at the greatest red shift,

Spirals at a high redshift is fine because the threshhold is only at z=5 at the most. I don't know what the highest redshift spiral is at this point, but I can tell you that there isn't much that can be said for saying that the galaxies of the past are like the galaxies of today.

What's very funny is that the Big Bang deniers like to take both sides of the battle on this one. In another thread I'm arguing with a Big Bang denier who says that there is TOO much structure evolution for the Big Bang to be true. Here you are saying there is not enough. What does the Big Bang model say, "Just Right!"


they say that there were more hydrogen filaments at large distances, they say the galaxies should be closer together at great distances without any evidence to support this,

Why don't you actually research this stuff before you come out with guns blazing? You make yourself seem backward when you lie like this.


they say the laws of physics don't hold for the initiation of the big bang

Faith-based mischaracterization. You say that it is inconsistent because it's at high energies... but we know that things change at higher energies. It may be theoretical right now, but it's far from "changing the laws of physics". In order for inflation to be true, it has to give us the universe we are in today... same laws of physics.


and that there is no such thing as before the big bang,

Well, I'm not a stickler for this one. If you want a "before" the Big Bang, be my guest. We don't have any idea what happens before inflationary models so all kinds of nonsense could be going on.


they say that there was an inflationary period for which there is no evidence.

The evidence is many and varied. Here (http://wlap.physics.lsa.umich.edu/umich/mctp/conf/2001/sto2001/guth/real/sld006.htm) is the most succinct summary of the evidence I could find (with the obvious ommission of the theoretical preference for a flat universe left off because it's not observational).



As Grote Reber's paper says, "The Big bang is Bunk", the universe is an "Endless, Boundless, Stable Universe" that preserves the cosmological principle.

With Einstein's cosmological constant, I guess exactly balancing the force of contraction. Okay, that seems like a pretty special case in my opinion. It does not explain the CMB, it does not explain the Hubble Expansion (unless you have a fountain of mass), and it does not explain nuclear abundances. One, two, three, you're out!



Quasars are much better explained if their red shift is intrinsic and they are not at the cosmolical rdistances of their red shift.

If I had a nickel for everytime you said this without any corroborating evidence, I'd have a whole lot of nickels


Their jets do not have to be so large and fast as to be relativistic.

What's your issue with relativistic jets?


Their brightness can be explained by their closeness.

Why can't quasars be intrinsically bright if they have intrinsic redshifts? We have mechanisms that allow for bright objects, so I think this is AT LEAST as reasonable as ascribing "intrinsic" redshifts that have no decent physical interpretation.


Their TEMPERATURE can be stellar since their spectra contains partially ionized elements that can only exist at stellar temperatures. (Despite what JS claims, I only said their spectra was stellar TEMPERATURE.)

The temperature of quasars is not well defined because they are not blackbodies. The only definitions that are given for TEMPERATURES are provided by the standard distant quasar model so JK has some 'splainin' to do.


Their spectra can be similar at all red shifts without evolving as big bangers expect to violate the cosmological principal.


Their spectra are NOT similar at all redshifts, though. Gunn-Peterson trough to wit.

I say that you have done a poor to horrible job at explaining away your prejudice JK. Thanks for trying.

D J
2003-Jan-26, 07:38 PM
On 2003-01-26 13:45, JS Princeton wrote:
The fact of the matter is that reionization did not occur uniformly because the universe was out of causal contact. This means that pockets had to form. What's so hard to understand about that? The local structure and anisotropy of the universe is perfectly reasonable with regards to the cosmological principle, likewise local hydrogen clouds are acceptable too. In fact, reionization requires local processes to do the reionization. This means that you expect inhomogeneity on the local level.



The cause itself for fhe reionization IE the Quasars pose a problem :

Quasars are very old. Some date back 12 billion years - to within a billion years of the Big Bang. That just doesn't seem to leave long enough for the host galaxies of quasars to come together and gather their supermassive black holes from a cloud of primordial gas and dust.

The Bad Astronomer
2003-Jan-26, 08:00 PM
On 2003-01-26 14:38, Orion38 wrote:
That just doesn't seem to leave long enough for the host galaxies of quasars to come together and gather their supermassive black holes from a cloud of primordial gas and dust.


This is not a scientific stance. "Seem" just isn't a good word to use when trying to make a scientific argument. You have to back up that feeling with physics. At the moment, current physics can produce galaxies not too long after the Big Bang. The models aren't perfect, but the science is still relatively young.

The Bad Astronomer
2003-Jan-26, 08:03 PM
On 2003-01-26 10:22, John Kierein wrote:
Big bangers think the cosmological principle is violated and that there are (or were) a lot more and varied hydrogen clouds at large distances than nearby. (The cosmological principal says that the large scale universe is pretty much the same everywhere and operates under our physics.)

Everywhere, but not necessarily everywhen. When looking back great disatnces, there is a significant lookback time, and astronomers expect things to be different, at least somewhat. If I look nearby, I don't see quasars (yes, I am assuming the BB is correct). Therefore, the Universe has changed over the past few billion years. Also, it makes sense to me that in the past there were more hydrogen clouds; by now a lot of them will have formed galaxies, stars, etc.

D J
2003-Jan-26, 08:18 PM
On 2003-01-26 15:00, The Bad Astronomer wrote:


On 2003-01-26 14:38, Orion38 wrote:
That just doesn't seem to leave long enough for the host galaxies of quasars to come together and gather their supermassive black holes from a cloud of primordial gas and dust.


This is not a scientific stance. "Seem" just isn't a good word to use when trying to make a scientific argument. You have to back up that feeling with physics. At the moment, current physics can produce galaxies not too long after the Big Bang. The models aren't perfect, but the science is still relatively young.


I found effectively an article introducing the dark matter as an explanation.
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v421/n6921/full/nature01330_fs.html

John Kierein
2003-Jan-26, 09:48 PM
On 2003-01-26 15:03, The Bad Astronomer wrote:


On 2003-01-26 10:22, John Kierein wrote:
Big bangers think the cosmological principle is violated and that there are (or were) a lot more and varied hydrogen clouds at large distances than nearby. (The cosmological principal says that the large scale universe is pretty much the same everywhere and operates under our physics.)

Everywhere, but not necessarily everywhen. When looking back great disatnces, there is a significant lookback time, and astronomers expect things to be different, at least somewhat. If I look nearby, I don't see quasars (yes, I am assuming the BB is correct). Therefore, the Universe has changed over the past few billion years. Also, it makes sense to me that in the past there were more hydrogen clouds; by now a lot of them will have formed galaxies, stars, etc.

The "perfect" cosmological principal says it is true "everywhen". That's what led Hoyle and Gold to the "steady-state" theory. The perfect cosmological principal was such a strong basis for cosmology that they had to invent mass creation from nothing to keep the universe at a constant density to preserve it. This of course is a violation of conservation of mass-energy. Nowadays cosmologogists have to violate all sorts of physics to make the big bang work including conservation of momentum and mass-energy and they also violate the cosmological principal. Even big bangers say there ARE quasars nearby; in the sense that they and Seyferts have red shifts of much less than 1 and microquasars are in our galaxy. Quasars at red shifts of .4 to 6.4 cover more than 90% of the time from the big bang.

JS says that quasars spectra vary, but Quoting the Keel article you referenced:
"It has been a long-standing curiosity that quasar spectra look much the same whatever the quasars' redshifts. Nearby objects and those seen at early cosmic times show much the same intensities of emission lines, which tell us about the relative abundances of such heavy elements as oxygen, nitrogen, aluminum, and iron. These are produced in massive stars and supernovae, with somewhat different ratios depending on the mass and age of stars involved. We can now examine quasars at redshifts as great as z=6.4, which is within about 800 million years of the beginning for the most likely cosmological parameters. The gas illuminated by the central engines of these quasars is no less rich in the products of stellar fusion than what we see here and now."
Thus the only variation is the lyman alpha forest which JS admits is not quasar spectra but from something outside the source.


<font size=-1>[ This Message was edited by: John Kierein on 2003-01-26 16:50 ]</font>

JS Princeton
2003-Jan-26, 09:56 PM
Galaxy and quasar seeding is a problem, but it's not an unsolvable one, Orion. It's actually something that is parametrized. When you are developing your model you have to take into account the fact that you need to have formed quasars at that time. All current models that are worth anything explain this feature.

What we don't understand right now is what the causes of these supermassive black holes are or why they seem to be found at the centers of nearly every galaxy we look at. There is no problem for formation time because nobody has a mechanism for formation. We're certain they aren't of stellar origin (you can actually show this using rather crude approximations and an extremely generous matter accumulation rate)... so there must be some other process out there.

No one ever said that there weren't issues left that need to be discovered. What we are simply saying is that paradigmatic problems take on a different shape than the ones that are presented by the cranks and the "deniers".

JS Princeton
2003-Jan-26, 10:01 PM
On 2003-01-26 16:48, John Kierein wrote:
Nowadays cosmologogists have to violate all sorts of physics to make the big bang work including conservation of momentum and mass-energy and they also violate the cosmological principal.

They do not violate the conservation of momentum or mass-energy. All of these values are conserved for all mainstream cosmological models. End of story.


Even big bangers say there ARE quasars nearby; in the sense that they and Seyferts have red shifts of much less than 1 and microquasars are in our galaxy.

But the special cases do not make the rule, and as has been pointed out, the deniers have no way of explaining these nearby objects. Why don't they exhibit the "intrinsic" properties that the others exhibit in exactly the same places and times? Sounds fishy to me.



Thus the only variation is the lyman alpha forest which JS admits is not quasar spectra but from something outside the source.


But not according to you, they aren't. The quasar spectra are different in absorption, that's what I was getting. You are the one that has to show why they are different since you insist that these are intrinsic properties. Go ahead and offer the proof!

dgruss23
2003-Jan-27, 03:50 AM
The evidence is many and varied. Here is the most succinct summary of the evidence I could find (with the obvious ommission of the theoretical preference for a flat universe left off because it's not observational).

The "evidence" at this site seems pretty weak. The first piece of evidence cited is that the universe is big. Wouldn't this be the case for all models of the universe whether it be the Big Bang, Steady State, or Arp's model? Or is there something specific to the Big Bang about the 10^90 particles cited on that page?

The second piece of evidence is the "Hubble Expansion". But Arp suggests that the interpretation of redshifts as velocity phenomenon is wrong. If he is right, then the universe is not expanding and therefore the Big Bang and inflation did not occur. So you will not convince Arp's supporters with this and it would seem to be flawed logic to cite the point in contention (expansion of the universe) as evidence for a phenomenon that would not exist if the other side is right.

The third piece of evidence is the homogeneity and isotropy of the universe. The difficulty with citing this as evidence for inflation is that the point is argued backwards. It would be correct to say that because the background radiation is so uniform, inflation is needed. Inflation was conceived as a fix to the problem of homogeneity of the universe and therefore that homogeneity cannot be cited as evidence that the inflation actually occurred.

JS Princeton
2003-Jan-27, 04:36 AM
On 2003-01-26 22:50, dgruss23 wrote:

The "evidence" at this site seems pretty weak.


Oh, you're absolutely right. It has no teeth, it's simply an introductory statement with the nuances of the argument removed. Of course, you could look at the other slides in the show to see what is meant by these rather glib reasons, but they all are very important reasons, let me assure you. Let's deal with these objections, though, one by one.



The first piece of evidence cited is that the universe is big. Wouldn't this be the case for all models of the universe whether it be the Big Bang, Steady State, or Arp's model?

Yes, this is getting at a few things here, but the most important of which is that an expanding universe that has to deal with something like an FRW metric necessarily has a problem with collapse or expansion out to a heat death. What we need is something that is "just right" or of a large scale but with stuff in it. This is hard to get unless you have inflation. Of course, if you deny a dynamical universe the argument doesn't work.... but that's a different issue entirely.


Or is there something specific to the Big Bang about the 10^90 particles cited on that page?

Indeed there is. The Big Bang explains this number of particles as one of the fundamental parameters. I believe this number includes all of the stuff (radiation and baryonic matter) that we can see. This number is a constraint on any theoretical model. Since we can give this order of magnitude estimate it isn't a huge constraint but what it does do is establish a density that can only be true for a limitted number of cosmologies you care to name.

In particular, in the class of dynamical cosmologies that give us this particular size of the universe we expect a NEARLY flat universe. This would seem to be quite a coincidence without inflation. Nevertheless, you are free to come up with such coincidental scenarios, just know that they aren't as likely to be accepted as "robust" a theory as inflation.


The second piece of evidence is the "Hubble Expansion". But Arp suggests that the interpretation of redshifts as velocity phenomenon is wrong.

No, Arp doesn't say that. He says SOME of the redshift contribution is intrinsic. Last I checked he still believed the universe was expanding. In fact, it's nearly impossible to find anyone who denies the dynamical universe since we see more than one piece of evidence for it. Of course, I've gone through this evidence before, so if you want to argue with it I suggest going to one of those threads. This thread really isn't about inflation either, but since no one seems to want to discuss it elsewhere I'm playing along with this little hijack.


If he is right, then the universe is not expanding and therefore the Big Bang and inflation did not occur.

That's a whole other ball of wax, you see. Inflation deals with the observational evidence as guiding the theory not the theory guiding the observational evidence. Inflationary theory doesn't "explain away" any of the observations that are made. Rather, inflationary theory makes predictions about things that haven't yet been observed. It can seem all very contrived because none of these things have been observed yet, and that's a legit criticism, but the difference between playing apologist for a theory and providing a theory that makes falsifiable predictions is a good one to learn in this business. Can you see the distinction?


So you will not convince Arp's supporters with this and it would seem to be flawed logic to cite the point in contention (expansion of the universe) as evidence for a phenomenon that would not exist if the other side is right.

I can see why this makes sense, except Arp supporters, in order to criticise inflation, necessarily step into my turf. Saying that inflation is "unreasonable" assumes that it is unreasonable in the context of itself... that is to say that if inflation "doesn't make observational sense" it must be because of something intrinsic about it. However, all these things that we've shown are observations and not meant to be "explained away" using intrinsic redshift models or steady-state nonsense. You see what I'm getting at?

This is very much like the geocentrists who say that the moon being tidally locked to the Earth doesn't make any sense (not that anyone actually MAKES that argument, I'm just using it as an example) and then expects us to defend it using a geocentrist's position. The fact is that the tidal lock is a model that is part and parcel to the non-geocentrist position. It cannot be dealt with using geocentrism. Similarly inflation cannot be dealt with without the Big Bang.



The third piece of evidence is the homogeneity and isotropy of the universe. The difficulty with citing this as evidence for inflation is that the point is argued backwards. It would be correct to say that because the background radiation is so uniform, inflation is needed. Inflation was conceived as a fix to the problem of homogeneity of the universe and therefore that homogeneity cannot be cited as evidence that the inflation actually occurred.


You're right in saying that it is not PARTICULAR to inflation, but inflation solves the problem. It is a bit of fancy back-engineering, you're right, and there are a lot of observationalists who don't like it for that reason. However, all these observationalists are Big Bangers... they don't like it because they haven't seen the evidence yet.

At this point we are at the cusp of being able to probe any inflationary epoch. Talking to many theoretical cosmologists would make you believe that inflation necessarily happened. In reality, the observational evidence isn't quite robust enough to say that with authority and no model has the ultimate say. In fact, slow-roll inflation has a number of problems as do many of the models you might consider. There is, however, good evidence that the universe did undergo an incredible period of expansion just because there are so many parameters that fit beautifully if such a thing happened. Is this definite evidence? Of course not! But it is a start to understanding where we're going.

What inflation is like right now is what Copernicus had when he proposed that the Sun was at the center of the Solar System. His idea didn't work out quite right, but it solved a lot of problems. It took more detailed observations by Brahe and eventually the work of Kepler and Newton to really pin down what the celestial mechanics were. It was a promising theory, "heliocentrism", motivated by parameters that seemed to fall into place well while they were awkward in the geocentric realm. Similarly with inflation.

John Kierein
2003-Jan-27, 02:39 PM
JS: I am making a distinction between the forest&trough and the basic spectra. The F&T are related to the redshift mechanism and their magnitudes are a function of the red shift. The F&T can easily explained as being caused by the same thing that causes the red shift whether the red shift is intrinsic or not, when that cause is the Compton effect. The F&T are difficult to explain when that cause is the doppler effect because it requires very complex motions, with clouds moving a various velocities.
I do not deny that there is such a thing as a doppler effect, in fact I work with it daily, but I believe the Compton effect also causes a red shift that looks just like it. Nature works in very similar ways, and, in fact several refereed papers have been written that make the Compton effect be a result of the doppler effect. This result comes basically from a choice of looking at the transfer of energy from the photon to the electron (or other mass) in the proper reference frame according to these papers. The change in wavelength becomes a result of the conservation of energy and momentum.

The big bang certainly DOES violate the conservation of mass-energy. It all starts with a "singularity" where the mass and energy are created from nothing. (There is also this magic zero-point energy that violates conservation laws but is easily explained in a static universe model). Steady-state theory just did the same thing as the big bang, but instead made the mass-energy be continuously created instead having a start in time. The static universes of Einstein and the one resulting from a Compton effect red shift do not violate this conservation but require that the mass energy has always been there and is compatible with the Perfect Cosmological principle. The "Endless, Boundless,Stable Universe" just isn't in fashion today. It's not as fanciful as the big bang and imaginative, but it's the way the universe really is.

JS Princeton
2003-Jan-27, 04:04 PM
On 2003-01-27 09:39, John Kierein wrote:
JS: I am making a distinction between the forest&trough and the basic spectra. The F&T are related to the redshift mechanism and their magnitudes are a function of the red shift. The F&T can easily explained as being caused by the same thing that causes the red shift whether the red shift is intrinsic or not, when that cause is the Compton effect.

Hmm, that's funny because you were the one who decided to go nuts when I said that the spectra changed over different redshifts and now wish to make a distinction. However, in order to do this, you have to be willing to admit that the "F&T" (your terminology) are in fact superimposed preferentially upon higher redshift quasars. If this is the case then is there an external mechanism at work that allows for these absorption features? Your handwaving and inability to account for this spectral signature only makes things worse.

To wit, if you believe that the redshifts are non-cosmological, these quasars are nearby and therefore the absorption features have to be explained by stuff associated with the quasar. I haven't seen you even attempt to tackle this thorn in your side.


The F&T are difficult to explain when that cause is the doppler effect because it requires very complex motions, with clouds moving a various velocities.

Actually, the motions that it requires are surprisingly simple. This is because we have a line-of-sight that we expect to see asymmetric forming of ionized and reionized regions. There is no problem of complex motions at all. In fact, you made up this problem in order to make it sound like the absorption effects could not be accounted for in quasar spectra when these effects are so well-accounted for they make intrisic redshifts look like real hooey. I wouldn't mind reading a referreed paper that explains how these "complex motions" are difficult to explain.



I do not deny that there is such a thing as a doppler effect, in fact I work with it daily, but I believe the Compton effect also causes a red shift that looks just like it.

Do you understand why the rest of us find this to be highly implausible?

I deal with the Compton effect in studies of the Sunyaev-Zeldovich effect. The things about this effect is that it does not behave in the same way as does redshift. The cross-section for photons is not the same across the spectrum. Therefore, you get scattering differences, and, in fact, an entirely different signal when you look at sources that have been Compton scattered by line-of-sight free electrons. Now, this isn't much a problem when you deal with a narrow range of energies and wavelengths (as Compton did when he was developing his misguided redshift corollary), but we now have spectrographs that can track the redshift into many different wavelength regimes and we DON'T see the non-linear wavelength dependence that is necessary for a Compton-like redshift. However, we've discussed this all before and you continue to refuse to answer the criticism.



Nature works in very similar ways, and, in fact several refereed papers have been written that make the Compton effect be a result of the doppler effect.

I think I know what papers you are referring to and if these are the ones that I'm thinking of you are grossly misrepresenting them.


The change in wavelength becomes a result of the conservation of energy and momentum.

This is a mechanism for the COMPTON effect but it is not a mechanism for a linear shift. Any scattering that is done, for instance, has other effects on the materials scattered. If you transfer momentum to a particle it necessarily increases in its energy content. This energy transfer should be visible as the excited particles that cause your "intrinsic" redshift reemit other radiation to get back to equilibrium. Where is this emission?



The big bang certainly DOES violate the conservation of mass-energy. It all starts with a "singularity" where the mass and energy are created from nothing. (There is also this magic zero-point energy that violates conservation laws but is easily explained in a static universe model).

This is utter baloney and you know ought to know it. First, the "singularity" is only an extrapolated event and has no physical evidence at this point. If you asked us where the stuff came from, the best we can do is point you to many different speculative theories about the cosmic atom and leave it at that. We have very little evidence for what happened much before inflation and so it's absurd for you to say that a part of the theory that has no model violates the conservation of energy and momentum.

In reality, there are a lot of processes that are well-documented that violate the conservation of momentum and energy both on large GR-scales and on the quantum level. This is part of the problem with these two theories: they violate these "fundamental" precepts of physics in irreconcilable ways. In fact, we have experimentally verified that these "violations" occur. For example, quantum tunnelling is a very real process that violates the conservation of energy. There are a lot of processes we can point to which violate these "fundamentals" and so it is disingenuous of you to paint the Big Bang as particularly unorthodox since it may seem to indicate a similar problem upon extrapolating back before we have viable models that are tethered down by observations.

Saying that the Big Bang violates the conservation of energy and momentum is like saying evolution violates the 2nd Law of Thermodynamics. It's based upon superstition and little else. It's almost impossible to argue against because there is no evidence to that effect.

I think there may also be a problem that you have separating out the Big Bang model from speculation. The singularity is a speculation. We cannot ever get to the singularity in any of the Big Bang models. We sometimes use the singularity as an illustrative point when teaching about the origins of the universe, but it is not a robust part of the theory at all. What is robust is everything up to the Time of Last Scatter and our high energy theories take us to the cusp of inflation. Before that, you basically are free to speculation what you will provided you realize you need to get out the conditions that allowed for the Big Bang universe (with the CMB and the nucleosynthesis and the Large Scale Structure and the Hubble Flow).

So, it's ludicruous to use the "singularity" as the part of the Big Bang model that violates the laws of conservation of energy and momentum because this singularity isn't even a part of the Big Bang model.



Steady-state theory just did the same thing as the big bang, but instead made the mass-energy be continuously created instead having a start in time.

But see, that's not actually the biggest problem with steady state. As we said before, there are other non-linear processes which don't conserve energy in the universe (quantum tunnelling). It's not ridiculous to assume that others could exist.


The static universes of Einstein and the one resulting from a Compton effect red shift do not violate this conservation but require that the mass energy has always been there and is compatible with the Perfect Cosmological principle.

There is no motivation for wanting to accept that the Perfect Cosmological Principle and a global conservation of mass/energy are what is needed in a theory of the universe. In fact, the first Principle is really just a fancy guess and nothing more. It is something that we have to measure to believe (and measure it and believe it we do for the Big Bang universe. The problem is with your universe that you have to explain how structure far away is smaller than structure nearby, for example, which seems to violate the "Perfect" principle). The Big Bang uses the Cosmological Principle only as a vague axiomatic starting point but isn't beholden to it. When it is discovered that the Universe was different in time, this wasn't so huge a problem when you aren't stubbornly stuck with perfection. It is why Einstein labelled the Cosmological Constant his "biggest mistake". If you can just get past the word "Principle" you can begin to see that the dynamical universe is the most elegant and simplest arrangement for the observations.


The "Endless, Boundless,Stable Universe" just isn't in fashion today. It's not as fanciful as the big bang and imaginative, but it's the way the universe really is.


Actually, it's far more fanciful because it has to explain away evidence like the CMB and redshifts and nucleosynthesis and structure evolution. It requires treating observations with kid gloves in order to make everything come out the right way; it's arbitrary, non-rigorous, and full of holes. That's not the model science takes... ever. Sorry.

dgruss23
2003-Jan-28, 02:38 AM
JS Princeton wrote: “No, Arp doesn’t say that. He says SOME of the redshift contribution is intrinsic. Last I checked he still believed the universe was expanding.”

Yes, Arp DOES say that the universe is not expanding and has for at least the last 10 years:

Narlikar&Arp 1993, ApJ 405, 51: “In our model the universe is not expanding, and the redshift arises from the age-redshift effect.”

Arp 1994, ApJ 430, 74: “If this empirical evidence had been heeded, the assumption that redshifts meant only velocity might never have been made, and the conclusion that the universe is expanding might never have been promulgated.”

Arp 1998, Seeing Red page 232: “The fact that there is no effect left over to be interpreted as a distance-velocity relation means that the universe is not expanding!”

Perhaps you have been confused by one of Arp’s recent papers in which he advocated a Hubble Constant of 55. But what you must understand is that this value is not viewed as a result of expansion in his model but rather a result of galaxy ages:

Narlikar&Arp (1993): “A dispersionless redshift-distance relation results for galaxies which are all of the same age.”

Arp (Seeing Red): “It turns out that for galaxies created at the same time, but seen at different distances, the m=at^2 solution requires these galaxies, which are seen at younger stages, to have exactly the same redshift as observed in the Hubble Relation. In fact, the slope of the relation, the observed Hubble Constant, is predicted within its error of measurement by only one number, the age of our galaxy.”

Geoff Burbidge and Morley Bell are astronomers that holds views more akin to the views you are attributing to Arp (ie intrinsic redshifts for some objects but overall expansion of the universe).

Of course I note these quotes not to advocate the Narlikar&Arp position, but to illustrate the major point of my previous post – that in making a sound logical argument you must be aware of what observations support what theories and further where the different theories become differentiated. It is important for those who wish to engage in the debate about Arp’s views to know exactly what he does believe about the expansion of the universe. And you cannot uphold a disputed observation as convincing evidence for a theory or hypothesis that builds upon the disputed fact. To say that the universe is expanding is evidence for inflation will not convince doubters of that expansion that inflation is real.

Nor was my intent to dispute whether or not inflation actually occurred. But in the interest of intellectual honesty, those that promulgate a Big Bang universe with inflation must acknowledge that inflation itself is not yet observationally confirmed (which you did acknowledge in your reply), but is instead a hypothesis that appears to be required to keep the observed homogeneity of the microwave background consistent with the currently favored Big Bang model.


JS Princeton wrote: That’s a whole other ball of wax, you see. Inflation deals with the observational evidence as guiding the theory, not the theory guiding the observational evidence. Inflation doesn’t “explain away” any of the observations that are made. Rather, inflationary theory makes predictions about things that haven’t yet been observed. It can seem all very contrived because none of these things have been observed yet, and that’s a legit criticism, but the difference between playing apologist for a theory and providing a theory that makes falsifiable predictions is a good one to learn in this business. Can you see the distinction?

This is the distinction I was trying to make. As you say, inflation is derived from observation – specifically the smoothness of the microwave background. But you must not forget that the microwave background is an observed phenomenon that is INTERPRETED as being a result of the Big Bang. Now the Big Bang may in fact predict features of the CMB that have been observed and this would add support to the theory. But the fact remains, the underlying foundation of the Big Bang is the assertion that galaxy redshifts are a result of expansion. This is in fact an interpretation that a minority do dispute. Again I am not arguing here that the universe is not expanding, but in terms of the logic of your argument to those who deny expansion of the universe, you cannot uphold expansion as evidence for inflation when they come knocking at your door saying the Big Bang is wrong.


JS Princton wrote: “What inflation is like right now is what Copernicus had when he proposed that the Sun was at the center of the Solar System. .

Perhaps – if it is ultimately demonstrated to be a genuine part of the Universe’s history – but Big Bang deniers will tell you that the theory which requires inflation as a fix (The Big Bang itself) is the modern geocentric model standing the the way of the progress of science.

JS Princeton
2003-Jan-28, 02:49 AM
dgruss, if you deny an expanding universe in general, inflation should not be an irreconcilable problem as JK has made it to be. Inflation is not observational evidence for the Big Bang, what I outlined was. It was HE who brought it up without a proper context and I properly contextualized it. It is illogical to say that the universe cannot be expanding because inflation doesn't make any sense because if you believe that the universe isn't expanding there is NO NEED for inflation. You are putting the cart before the bull as it were, if you think that inflation can be used as a counterargument against an expanding universe. Inflation is just a result of expansion, after all. That's all.

Thanks for bringing up Arp's past, though I think now he has basically admitted that he has no mechanism for to explain the cosmological redshift-distance relation. He tries to deny an expanding universe earlier in his career by denying that there was a redshift distance relation. Now that is has become apparent that that can no longer be true he doesn't talk about the issue much and publishing an H=55 km/sec/Mpc paper does not do much for you if you don't believe the universe is expanding

dgruss23
2003-Jan-28, 03:06 AM
JS Princeton wrote: You are putting the cart before the bull as it were, if you think that inflation can be used as a counterargument against an expanding universe. Inflation is just a result of expansion, after all. That's all.

I am in agreement that inflation fits within the context of the Big Bang. Is the argument JK is making with regard to inflation simply that if inflation did not occur the Big Bang must be wrong because the current Big Bang Standard requires inflation to explain the microwave background?


JS Princeton wrote: Thanks for bringing up Arp's past, though I think now he has basically admitted that he has no mechanism for to explain the cosmological redshift-distance relation.

Arp's proposed mechanism for intrinsic redshifts is found in Narlikar&Arp (1993). The model allows for mass to vary over time - the age-redshift effect as it is described. Of course the model is only viable if the universe is not expanding.

John Kierein
2003-Jan-28, 03:17 AM
JS wrote: "This is a mechanism for the COMPTON effect but it is not a mechanism for a linear shift. Any scattering that is done, for instance, has other effects on the materials scattered. If you transfer momentum to a particle it necessarily increases in its energy content. This energy transfer should be visible as the excited particles that cause your "intrinsic" redshift reemit other radiation to get back to equilibrium. Where is this emission?"

I was worried about quasar red shifts and the solar red shift when I wrote my paper that was published back in '68 in Solar Physics. That's when I discovered the red shift from the Compton effect. At the same time my paper was in press, I discovered Reber's paper in the J. Franklin Institute.
(Reber, G., 1968 J. Franklin Inst., 285, 1.)

I had never heard of Grote before this. I was floored to discover that he too said the cosmological red shift was due to the Compton effect. But he said it for entirely different reasons than I did. He did it to explain the source of the energy he discovered at hectometric wavelengths. That's where the energy is. This energy is at very long wavelengths and is very difficult to map, although Grote's maps at these wavelengths have been grossly confirmed with poorer antennas by some Goddard Space Flight Center scientists from New Zealand. Grote found some openings in the ionosphere during solar minimum winters and measured this radiation to be surprisingly bright and extragalactic. A small version of his maps can be seen here,

http://personal.nbnet.nb.ca/galaxy/G_Reber.html
but a really good description of what was the world's largest radio telescope array and details of his measurements can be better found in the above referenced paper. I don't think any other radio telescope has ever been built with as much "light" or "radio" gathering power and with such nice low sidelobes although the VLA is much bigger in resolution size. It covered several acres and was steered horizontally. Reber's measurements showed the background at 144 meters and 500 meters to be surprisingly bright, much brighter temperature-wise by six orders of magnitude than the CMBR! Where was this radiation coming from? Grote knew it was extragalactic because it was dim along the Milky Way and at the LMC where the material there was absorbing it. Grote finally realized it was the radiation from intergalacitic electrons that had been accelerated by the Compton effect and that the Compton effect must be causing the cosmological red shift. That where the energy is. (I think this energy causes gravity, too.) I had generalized from the intrinsic special cases of the solar red shift and the quasar red shift to the cosmological case; Grote had started with the cosmolgical case to explain his observations. He and I eventually became kindred friends and corresponded quite a bit. I arranged for some talks he gave at the U. of Colorado and at the U.'s planetarium. He also believed the solar red shift was Compton, but I never got much comment from him about the quasar red shift being intrinsic except some agreeable nods.

John Kierein
2003-Jan-28, 03:34 AM
dgruss23 says: "But the fact remains, the underlying foundation of the Big Bang is the assertion that galaxy redshifts are a result of expansion."
I heartily agree. My brother is the weatherman on Channel 4 in Washington DC and often gets to interview members of the scientific community. He had a chance to ask Carl Sagan once a few years: What if the red shift were due to the Compton Effect? Carl's response was: "Why that would change EVERYTHING." He didn't say: oh, that's wrong. He just iterated what dgruss23 says; namely that the doppler interpretation is the foundation of the big bang. Without it there's no big bang. CMBR smoothness, element formation, or anything else notwithstanding.

JS Princeton
2003-Jan-28, 06:17 AM
Well, we'll get answers about the large wavelength background with improved observations. Preliminary results from these background surveys to do not corroborate a uniform background but rather point sources. This does not seem to bode well for a theory of plasma interactions causing redshift.

John Kierein
2003-Jan-28, 03:26 PM
On 2003-01-28 01:17, JS Princeton wrote:
Well, we'll get answers about the large wavelength background with improved observations. Preliminary results from these background surveys to do not corroborate a uniform background but rather point sources. This does not seem to bode well for a theory of plasma interactions causing redshift.

Just what background surveys are you referring to? The only ones I'm aware of were way less resolution than Reber's. Some GSFC scientists built a small antenna in New Zealand that corroborated Reber's measurements, but again with poor resolution. These measurements can only be made at solar minimum during the winter along the agonic line in either Tasmania, New Zealand or Canada. Reber nearly succeeded in getting the Herzberg group in Canada to fund some observations, but ran into the usual budgetary problem before the sun activity began to pick up again. The RAE just used vee antennas with exceedingly low resolution and high sidelobes. I presented a paper to the AIAA asking for a low frequency antenna on the backside of the moon, which is one of the few ways to get this data routinely. We've also pushed to get some sounding rocket shots over antennas using SF6 or hydrogen to temporarily deplete the ionosphere and create an observation window. Some such SF6 shots have been made over the Aricebo radar farm but the priorities were for ionospheric studies and the antenna farm had to operate in its usual transmit mode rather than a recieve mode and no radio astronomy data was able to be taken. Unfortunately, Reber's fine Tasmanian antenna farm low frequency observatory was dismantled after the last solar minimum. At least his work in Tasmania has stimulated a good radio astronomy program at the University in Hobart.

JS Princeton
2003-Jan-28, 05:33 PM
JK, are you really that far out of the loop? I can't get a handle on you. It's like all of the knowledge you have of observational surveys is taken from the 1970s or earlier.

Karl
2003-Jan-28, 09:27 PM
On 2003-01-28 01:17, JS Princeton wrote:
Well, we'll get answers about the large wavelength background with improved observations. Preliminary results from these background surveys to do not corroborate a uniform background but rather point sources. This does not seem to bode well for a theory of plasma interactions causing redshift.


I think the general low frequency background is accepted to be caused by synchrotron radiation in the galactic magnetic field, and scattered off of the interstellar medium.

Fleishmann paper (http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1995A%26A...293..565F&data_type=PDF_HIGH&type=PRINTER&ext=.pdf)

Edit to shorten link

<font size=-1>[ This Message was edited by: Karl on 2003-01-28 16:29 ]</font>

JS Princeton
2003-Jan-28, 09:38 PM
Right on, Karl.

Zathras
2003-Jan-28, 09:46 PM
Now, isn't bremstrahlung also a signifcant component of the low frequency region? This might be part of my fading memory, but I seem to recall that being true.

D J
2003-Jan-28, 09:56 PM
On 2003-01-28 16:27, Karl wrote:
I think the general low frequency background is accepted to be caused by synchrotron radiation in the galactic magnetic field, and scattered off of the interstellar medium.

Fleishmann paper (http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1995A%26A...293..565F&data_type=PDF_HIGH&type=PRINTER&ext=.pdf)


Who discovered an explained the cause and origin of the Synchrotron radiation?:
http://public.lanl.gov/alp/plasma/synchrotron.html

http://public.lanl.gov/alp/plasma/EMspectrum_observ.html
Synchrotron radiation is named after the particle accelerators developed in the 1930's and 1940's to produce high-energy electrons. In 1950 Hannes Alfven, Nicolai Herlofson, and Karl Keipenheuer brought this form of plasma radiation to astronomers' attention. Alfven, who later won a Nobel prize in physics for his solar studies, proposed that streams of electrons move at nearly the speed of light along magnetic-field lines not only in Earth's magnetosphere and above the Sun, but also throughout the cosmos.

<font size=-1>[ This Message was edited by: Orion38 on 2003-01-28 16:58 ]</font>

Karl
2003-Jan-28, 10:20 PM
On 2003-01-28 16:46, Zathras wrote:
Now, isn't bremstrahlung also a signifcant component of the low frequency region? This might be part of my fading memory, but I seem to recall that being true.


Synchrotron radiation is occasionally called magnetic bremsstralung.

Synchrotron radiation is emitted when a fast electron interacts with a magnetic field. A magnetic field in an area an electron is traveling in will cause the electron to change direction by exerting a force on it perpendicular to the direction the electron is moving. As a result, the electron will be accelerated, causing it to radiate electromagnetic energy. This is called magnetic bremsstrahlung or synchrotron radiation (after radiation observed from particle accelerators by that name). If the electrons and the magnetic field are energetic enough, the emitted radiation can be in the form of X-rays.

http://heasarc.gsfc.nasa.gov/docs/astroe_lc/spectrum/xray_techc.html

Karl
2003-Jan-28, 10:27 PM
On 2003-01-28 16:56, Orion38 wrote:

Who discovered an explained the cause and origin of the Synchrotron radiation?:
http://public.lanl.gov/alp/plasma/synchrotron.html

And Alfven's work is used where applicable to solve a number of astrophysical problems, as it should be.

<font size=-1>[ This Message was edited by: Karl on 2003-01-28 17:28 ]</font>

John Kierein
2003-Jan-28, 10:42 PM
I think the general low frequency background is accepted to be caused by synchrotron radiation in the galactic magnetic field, and scattered off of the interstellar medium.

Fleishmann paper (http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1995A%26A...293..565F&data_type=PDF_HIGH&type=PRINTER&ext=.pdf)


But this is not inconsistent with the acceleration of the intergalactic electrons by the Compton effect to provide the energetic electrons for the synchroton radiation.

D J
2003-Jan-28, 10:44 PM
On 2003-01-28 17:27, Karl wrote:


On 2003-01-28 16:56, Orion38 wrote:

Who discovered an explained the cause and origin of the Synchrotron radiation?:
http://public.lanl.gov/alp/plasma/synchrotron.html

And Alfven's work is used where applicable to solve a number of astrophysical problems, as it should be.

<font size=-1>[ This Message was edited by: Karl on 2003-01-28 17:28 ]</font>


Agreed.However this is interesting than he also start the basis for a new cosmology based on Plasma.

JS Princeton
2003-Jan-28, 11:39 PM
On 2003-01-28 17:42, John Kierein wrote:


But this is not inconsistent with the acceleration of the intergalactic electrons by the Compton effect to provide the energetic electrons for the synchroton radiation.


It certainly doesn't support the "uniform" scattering theory across all lines of sight causing all redshifts.

Karl
2003-Jan-29, 05:35 AM
On 2003-01-28 17:42, John Kierein wrote:
But this is not inconsistent with the acceleration of the intergalactic electrons by the Compton effect to provide the energetic electrons for the synchroton radiation.


Inverse Compton scattering has certainly been noted as an acceleration mechanism for electrons. AND is consistent with electrons spiraling in the galactic magnetic field and producing the observed low frequency galactic background radiation.

DStahl
2003-Jan-29, 06:31 AM
Way up the thread John and JS mentioned conservation of energy and momentum relating to the genesis of the universe. It seems to me that I have read that if the total mass/energy of the universe is expressed as a positive quantity then it may well be exactly balanced by the total gravitational energy of the universe, which would be expressed as a negative quantity. In our understanding of the physics of inflation I believe that this ratio is driven very quickly toward one.

As someone or other said, the universe may well be the ultimate free lunch--it may not violate conservation laws!

I'll see if I can hunt up some links.

[later]

OK, here's an Astronomical Society of the Pacific article (http://www.astrosociety.org/pubs/mercury/31_02/nothing.html). Quote:

"The idea of a zero-energy universe, together with inflation, suggests that all one needs is just a tiny bit of energy to get the whole thing started (that is, a tiny volume of energy in which inflation can begin). The universe then experiences inflationary expansion, but without creating net energy."

"What produced the energy before inflation? This is perhaps the ultimate question. As crazy as it might seem, the energy may have come out of nothing! The meaning of "nothing" is somewhat ambiguous here. It might be the vacuum in some pre-existing space and time, or it could be nothing at all – that is, all concepts of space and time were created with the universe itself."

"Quantum theory, and specifically Heisenberg’s uncertainty principle, provide a natural explanation for how that energy may have come out of nothing....Perhaps many quantum fluctuations occurred before the birth of our universe. Most of them quickly disappeared. But one lived sufficiently long and had the right conditions for inflation to have been initiated. Thereafter, the original tiny volume inflated by an enormous factor, and our macroscopic universe was born. The original particle-antiparticle pair (or pairs) may have subsequently annihilated each other – but even if they didn’t, the violation of energy conservation would be minuscule, not large enough to be measurable."

"If this admittedly speculative hypothesis is correct, then the answer to the ultimate question is that the universe is the ultimate free lunch! It came from nothing, and its total energy is zero, but it nevertheless has incredible structure and complexity. There could even be many other such universes, spatially distinct from ours."



<font size=-1>[ This Message was edited by: DStahl on 2003-01-29 01:36 ]</font>

Chip
2003-Jan-29, 10:13 AM
On 2003-01-29 01:31, DStahl wrote:
"...It seems to me that I have read that if the total mass/energy of the universe is expressed as a positive quantity then it may well be exactly balanced by the total gravitational energy of the universe, which would be expressed as a negative quantity. In our understanding of the physics of inflation I believe that this ratio is driven very quickly toward one..."

To the 'cosmic soup' of this thread I'd like to add one other ingredient. What has been termed "CP Violation" may also present a slight hint of evidence that the early universe favored matter over antimatter. Apparently the basic laws of particle physics don't favor one over the other, but somehow needed to for the early universe to get started. One of those wonderful paradoxes that imply that the early universe was very different than the cosmos that is 'now' observed somewhat closer to us. (If the early big bang was perfectly matter and antimatter balanced, instead of very slightly tilted toward matter, we wouldn't be here.) One of the great questions has been, what caused this imbalance? From what I've read, "CP Violation" is a process by which particles of matter transmute at a different rate than anti-matter counterparts. Researchers who study K mesons first noted this.

I read also in Sky & Telescope last year that scientists working with more massive B mesons have observed matter / anti-matter asymmetry. This doesn't answer the question of the origin of the universe, but just after, if such asymmetry is built into the nature of matter itself as a result of its interaction with anti-matter, then such asymmetry is among the fundamental processes of the early universe. It could be an important factor. Perhaps both mass/gravity balance and matter/anti-matter asymmetry being present.

JS Princeton
2003-Jan-29, 02:12 PM
CP violation. It is really a very slight effect and has to do with charge and parity of the products of a reaction having different decay times. There is also something called "CPT" violation that puts time as a variable into the mix. Whether the asymmetry (which we know exists, we just don't know necessarily why) is caused by just CP or a combination of CP and CPT is not yet clear. However, the constraint on the number of observed baryons in the universe compared to the number of CMB photons tells us what the asymmmetry had to be from observations.

This is one of the places where particle physics and large-scale cosmology converge. It's really quite profound.

John Kierein
2003-Jan-29, 03:21 PM
On 2003-01-29 00:35, Karl wrote:


On 2003-01-28 17:42, John Kierein wrote:
But this is not inconsistent with the acceleration of the intergalactic electrons by the Compton effect to provide the energetic electrons for the synchroton radiation.



Inverse Compton scattering has certainly been noted as an acceleration mechanism for electrons. AND is consistent with electrons spiraling in the galactic magnetic field and producing the observed low frequency galactic background radiation.

I'm sorry, but inverse Compton effect is the transfer of energy and momentum from an electron to a photon. It is very rare and occurs only for head-on collisions with relativistic electrons according to MacDonald of Princeton. It causes deceleration not acceleration of electrons. As for the Fleishman ideas, while it is not inconsistent with the Compton effect, it does not agree with Reber's maps which show a dim spot at the magellanic cloud where this extragalactic object absorbs the radiation. Fleishman's stuff is theory; Reber's is observation. Observations at hectometric wavelengths from below the ionosphere can only be made during solar minimums and have not been made well since Reber's antenna was dismantled.


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JS Princeton
2003-Jan-29, 05:06 PM
There are many different hectometric studies going on and that have gone on, John. Go to NASA's abstract search and look for yourself. Off the top of my head I can think of WAVES on WIND and HiRAS. I know there are more.

John Kierein
2003-Jan-29, 09:28 PM
I am familiar with the WIND WAVES experiment. It is nice as far as it is able to go. Like the Radio Astronomy Explorer that went to the moon it consisted of long wire booms. We had similar booms on the CRRES spacecraft with which I was heavily involved. These booms are capable of measuring the level of radiation and the variation in strength, but have very, very poor directional resolution and have very high sidelobes. They can generally detect the direction of the sources but cannot map in any detail dim spots against a bright background. Reber's antenna in contrast consisted of several acres (3520 feet in diameter with 192 dipoles on telephone poles high above the ground -that's 223 acres!) of antenna on high poles that was steered electrically in one direction and used the earth's rotation to steer in the other and had excellent directionality, sensitivity and resolution. It turned out that its low sidelobes were perfect for detecting the dim spots against a bright background. Reber wanted to map the hectometric sky at these wavelengths and found it to be the negative of the shorter wavelength sky much to his surprise, with a brighter than expected general background.
By the way, the Arecibo dish advertises itself as the world's largest, but it's only about 20 acres. It operates at much shorter wavelengths. I've been out on the beam over the Arecibo dish. It's pretty cool. Only a few of us were allowed out at a time.
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Chip
2003-Jan-29, 10:40 PM
On 2003-01-29 09:12, JS Princeton wrote:
"CP violation. It is really a very slight effect and has to do with charge and parity of the products of a reaction having different decay times. There is also something called "CPT" violation that puts time as a variable into the mix. Whether the asymmetry (which we know exists, we just don't know necessarily why) is caused by just CP or a combination of CP and CPT is not yet clear. However,...the asymmmetry had to be from observations..."
Thanks for clarifying this. I have to read more about it. (If you could suggest where to start, that would be helpful.) Much appreciated. /phpBB/images/smiles/icon_wink.gif

Just while looking around a little online, I found this interesting Website: http://www.atomic.princeton.edu/romalis/

JS Princeton
2003-Jan-30, 05:57 AM
What you've failed to mention, JK, is that now radio observations are rarely if ever done from a single telescope because interferometry is that much better.

D J
2003-Feb-09, 10:00 PM
Correct me if I am wrong but that study seem talking about an intrinsic redshift of Z~3 with decreasing redshift, galaxies forming in the denser regions, may contribute an increasing part of the Ly absorption cross-section.Later in the study they said depending of the line of sight of the gas clouds so this seem to implying that high redshift Quasars and the absorbtion spectra giving the Layman Alpha forest depend only if the Quasars light passe trough this highly Ionized medium -IE galaxies forming in the denser regions, may contribute an increasing part of the Ly absorption cross-section-.

Question at what distance are located those denser regions?


Recent progress with cosmological hydro-simulations based on hierarchical structure formation models has led to important insights into the physical structures giving rise to the forest. If these ideas are correct, a truely inter- and proto-galactic medium [at high redshift (z ~ 3), the main repository of baryons] collapses under the influence of dark matter gravity into flattened or filamentary structures, which are seen in absorption against background QSOs. With decreasing redshift, galaxies forming in the denser regions, may contribute an increasing part of the Ly absorption cross-section
http://nedwww.ipac.caltech.edu/level5/Sept01/Rauch/Rauch_contents.html

http://nedwww.ipac.caltech.edu/level5/Sept01/Rauch/Rauch5.html

<font size=-1>[ This Message was edited by: Orion38 on 2003-02-09 17:32 ]</font>