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Fraser
2006-Oct-02, 02:58 AM
Dark matter . . . What is it? Nobody knows for sure, but it's definitely there. Or maybe it's not there, and we just need some redefinition of gravity at vast scales. ...

Read the full blog entry (http://www.astronomycast.com/extragalactic/the-search-for-dark-matter/)

searlesgold
2006-Oct-03, 11:21 AM
Hi Fraser....

Recently I had a conversation with the very well known cosmotoligist, Russ Croman. He pitched the Question to him
"What is Dark Matter" He promptly replied to me....
"That's a Good Question!" and went on to say, "Nobody Knows!"

I have posted my question about it many times and I never receive
any replies! This is my theory about the unknown......

I happen to believe in INFINITY! Infinity is primarally has two major componets: Endlessness and Timelyness, no beginning and no ending to either! There never has been a moment, when infinity was not existing! Why is it so difficult to believe that infinity does not have COLOR?? In other words, at night when we point our eyes away from Earth towards the sky and focus on the "Dark Matter" between any form of light, (stars,planets,etc.)
and believe the "Darkness" is the color of Infinity...BLACK!

The idea that the "Big Bang" theory that supossedly started the beginning of the Universe is absurd! What was existing before the Big Bang!?? Common sence tells us there had to be Something!
If nothing else, there had to be infinity and Temporature!
Note: the absence of heat, temporature will Drop! I don't think we know how far down temporature can drop?

Much more, but it is after 4am and I'm ending here!

Regards,
Gary / searlesgold
g-man=coin@sbcglobal.net

punkrockbong151
2006-Oct-03, 01:29 PM
Dark matter . . . What is it? Nobody knows for sure, but it's definitely there. Or maybe it's not there, and we just need some redefinition of gravity at vast scales. ...

Read the full blog entry (http://www.astronomycast.com/extragalactic/the-search-for-dark-matter/)

:hand: Dark matter i beleive is ther, i agree with astronemers, it is beleived it is there because objects are beleive to pass and then swing or turn as if ther was some planet or peice of matter using gravity to change it's route, i beleive in most cases that this would be a black hole, which is thought to have massive gravitional pull, even pulling light into itself as we all kno, hence making it impossible to shed any light at all to make even a slight prediction of wat is around it :lol:

John Mendenhall
2006-Oct-04, 04:56 PM
Russ Croman will be overjoyed to learn that he is a beautician. All those years of education wasted trying to become a cosmologist.

More constructive suggestion: write comments in a word processor and use the spelling and grammar checker, then copy to here. I make plenty of mistakes, this procedure catches most of them.

Relevant to the discussion at hand, I have problems with the entire dark matter/dark energy scenario. Be back later after some source checking.

Kevn
2006-Oct-04, 05:07 PM
Hey Pamela.

During the 'cast, you referred to the "ballet cluster" where the recent dark matter evidence was found. But it's spelled "Bullet" on APOD and other places. Just wondering.

Great episode though.

Also, Cosmic Variance has a great image about that cluster and dark matter, in the spirit of the classic demotivational posters...


Bullet Cluster "Motivational" Poster (http://cosmicvariance.com/wp-images/dmmotivator_01.jpg)

A friend of mine says that
...the astro community (which I find hard to comprehend oftentimes) would rather believe that we don't understand anything (e.g. MOND=general relativity is wrong for no good reason) than believe that new particles exist beyond those in stars...

toneyvr
2006-Oct-04, 07:03 PM
It seems to me that if Dark Matter (DM) is particulate and exerts gravitational influence, should it not agglomerate? Shouldn't we get DM planets, or at least planets and stars combined with DM? Or is it that WIMPS generate gravity, but are unaffected by it? Hmm!

WaxRubiks
2006-Oct-04, 08:45 PM
what is dark matter?, that is a very dark matter.......

Blob
2006-Oct-05, 12:23 AM
During the 'cast, you referred to the "ballet cluster" where the recent dark matter evidence was found. But it's spelled "Bullet...

Hum,
strangely i thought i heard it that way as well...
i just put it down to a Freudian slip.

Kevn
2006-Oct-05, 02:44 AM
So that means Pamela secretly wants to be a ballerina? Cool!!:lol: :dance:

Blob
2006-Oct-05, 11:19 AM
Hum,
don't we all?
, or she may have subconsciously spotted (for example) a tutu, during Frasers interview.

BTW, there is more info about the bullet cluster (1E0657-56) on this thread (http://www.bautforum.com/showthread.php?t=45700).

M. Mayer
2006-Oct-05, 12:19 PM
I have a couple of questions for Pamela Day from the Dark Matter Podcast:
1) Why do you refer to gravity bending light? Doesn't gravity warp space and light just travel along this warped space? Is this type of conceptual shortcut possibly responsible for our lack of understanding of what is going on with dark matter/energy?

2) You mentioned that ther outer objects of galaxies and clusters are moving faster than expected, more like a rigid platter, rather than slowing down. I assume this slowing down is what we observe in spiral galaxies. Rather than additional dark matter, could there be an interaction between matter that we can only observe at this scale?

Thank you in advance your attention to these questions.

punkrockbong151
2006-Oct-05, 09:07 PM
some of u ppl r not even close to the subjusct, this is a space and astronomy forum about dark matter, don't talk about tutu's and other crap:eh: :mad:

Blob
2006-Oct-05, 09:39 PM
Hehe,
sry, got carried away on a musical thread posting day.
Anyway, there is another exciting bit of research (http://www.bautforum.com/showthread.php?t=47611) that has appeared recently that you may want to peruse.

It seems we now actually have pieces of the puzzle

George
2006-Oct-05, 10:03 PM
Nice show, once again. :clap:

Trying to come up with suggestions for you.....Since I've gotten used to this place (BAUT), prior to air time, you might want to post any related images onto the respecitve thread and refer to them in your podcast so we can enjoy an even more colorful program.

antoniseb
2006-Oct-06, 12:06 PM
It seems to me that if Dark Matter (DM) is particulate and exerts gravitational influence, should it not agglomerate? Shouldn't we get DM planets, or at least planets and stars combined with DM? Or is it that WIMPS generate gravity, but are unaffected by it? Hmm!

Hi toneyvr, welcome to the BAUT forum.

A lot of people have the idea that gravity somehow can make things collect together, but it takes more than gravity. It takes some kind of force to stop the relative motions of two objects when they get collide. Dark matter doesn't get stopped when it goes by any other matter (dark or otherwise), except *very* rarely. We have a few mutually exclusive ideas about why, so we can't say we know yet. In short, dark matter will not agglomerate densely enough to form dark-matter planets.

John Mendenhall
2006-Oct-06, 07:39 PM
If you can't see it, and you can't detect it, you can attribute any kind of properties you want to it.

Let's look at the dark matter arguments again.

1. The outer regions of spiral galaxies and galaxies in clusters move too fast to be held in orbit by the amount of gravitating matter that we detect.

2. If Newtonian mechanics holds, a lot more of more or less evenly distributed gravitating mass is required.

3. If a whole lot more mass is required, then it must be invisible and/or very difficult to detect. We certainly haven't had any luck so far, and I'm not impressed with the Bullet Cluster work.

I'm not happy with the MOND work, either, but I think it has less smoke and mirrors than dark matter. Fundamentally, I think we're missing something. Remember what a stew physics was in after Michelson/Morley and before Einstein.

Blob
2006-Oct-06, 08:25 PM
Hum,
you are perhaps not aware of all the recent research that has basically discredited MOND as a viable alternative to DM.

It is true that we haven`t see darkmatter, but we can detect it, and we can even attribute a few properties that it must have to fit with the observations.

For example, researchers from the University of Cambridge Institute of Astronomy claim to have calculated that dark matter only comes in clumps larger than about 1,000 light-years across, implying an average speed of dark matter particles of 9 km/s, a density of 20 amu/cm³, and temperature of 10,000 kelvins.

http://en.wikipedia.org/wiki/Dark_matter

eremon
2006-Oct-10, 05:24 AM
Dark matter . . . What is it? Nobody knows for sure, but it's definitely there. Or maybe it's not there, and we just need some redefinition of gravity at vast scales. ...
I don't understand why dark matter halos wouldn't be subject to the same inertial tendencies as detectable matter. That is, why don't they slow down just as the outer stars are expected to according to the standard model. It seems to me that if dark matter halos explain the uniform rate of rotation of inner and outer objects in a spiral galaxy, then they must actually be dictating that rate of rotation. Perhaps that's why the ratio of dark matter to detectable matter is estimated to be about 5:1.

Can anyone enlighten me on this?

Blob
2006-Oct-10, 11:38 AM
Hum,
indeed,
by having massive amounts of `stuff` in halos it can explain away the linear (for the most part) rotation graph of the galaxy.

But it has to be said we don't know very much about the source of inertia,
There are theories that make use of virtual photon/matter interactions to create mass/inertia, but how that may apply to darkmatter we don't know.
Gravitational attraction and inertia (or even mass) may not be simply connected.

It seems according to recent theories that dark matter has the same gravitational properties (± 10%) as normal matter. And the reason why it is in halos (rather than slowing down and clumping together at the centre of galaxies) seems to be that it is fasts moving and collisionless

Blob
2006-Oct-10, 11:40 AM
Title: Spin alignment of dark matter haloes in filaments and walls
Authors: Miguel A. Aragón-Calvo, Rien van de Weygaert, Bernard J. T. Jones, J.M. Thijs van der Hulst

The MMF technique is used to segment the cosmic web as seen in a cosmological N-body simulation into wall-like and filament-like structures. We find that the spins and shapes of dark matter haloes are significantly correlated with each other and with the orientation of their host structures. The shape orientation is such that the halo minor axes tend to lie perpendicular to the host structure, be it a wall or filament. The orientation of the halo spin vector is mass dependent. Low mass haloes in walls and filaments have a tendency to have their spins oriented within the parent structure, while higher mass haloes in filaments have spins that tend to lie perpendicular to the parent structure.

Read more (http://arxiv.org/PS_cache/astro-ph/pdf/0610/0610249.pdf) (288kb, PDF)

<attachment>
Lefthand panel: Particles inside a sub-box of 37.5 × 75 × 100 h-1 Mpc. For reasons of clarity only a small fraction of the total number of particles is shown.
Central panel: filaments delineated by a subsample of the particle distribution. At each particle location we have plotted the filament vector eF, indicating the direction locally parallel to the filament.
Righthand panel: wall particles detected in the same sub-box: at each wall particle we plot the wall vector eW. Two walls can be clearly delineated: one seen edge-on (dashed outline) and one seen face-on (solid outline).

eremon
2006-Oct-10, 02:19 PM
Hum,
indeed,
by having massive amounts of `stuff` in halos it can explain away the linear (for the most part) rotation graph of the galaxy.

But it has to be said we don't know very much about the source of inertia,
There are theories that make use of virtual photon/matter interactions to create mass/inertia, but how that may apply to darkmatter we don't know.
Gravitational attraction and inertia (or even mass) may not be simply connected.

It seems according to recent theories that dark matter has the same gravitational properties (± 10%) as normal matter. And the reason why it is in halos (rather than slowing down and clumping together at the centre of galaxies) seems to be that it is fasts moving and collisionless
I must say that, despite the recent observations, dark matter and dark energy strike me as black box explanations for phenomena that are anomalous with respect to mainstream theory. They seem like place-holders for huge unknowns in current cosmological thinking. While such constants have often been posited in the evolution of theory—witness Einstein's cosmological constant—I would expect them to just gently tweak the data to make it fit. The fact that dark matter and energy account for 94% of the universe seems an awful lot like the tail wagging the dog. Why are so many mainstream scientists prepared to make a leap of faith to something that seems so far-fetched? Is it possible that we're becoming too enamored of our own favorite theories?

eremon
2006-Oct-10, 02:28 PM
Hum,
It seems according to recent theories that dark matter has the same gravitational properties (± 10%) as normal matter. And the reason why it is in halos (rather than slowing down and clumping together at the centre of galaxies) seems to be that it is fasts moving and collisionless
I recall seeing something about friction-produced static electricity in the earliest moments of the big-bang being required to initiate the accumulations of mass that have culminated in the large-scale structures of the universe.

Blob
2006-Oct-10, 05:45 PM
I must say that, despite the recent observations, dark matter and dark energy strike me as black box explanations for phenomena that are anomalous with respect to mainstream theory. They seem like place-holders for huge unknowns in current cosmological thinking.

Hum,
indeed it is good to view the term `dark matter` as just a place-holder.
However, having said that, there is little doubt nowadays amongst cosmologists that darkmatter exists - we can see through observation that it exists.

The rule is that, to paraphrase Richard Feynman, "If the theories and mathematics do not match the observations, then they are wrong."

As far as the current theories go, the only leaps needed are to what actual form that `shadow substance` takes.

(No-one is forcing anyone to jump)...

StarStryder
2006-Oct-12, 03:08 AM
During the 'cast, you referred to the "ballet cluster" where the recent dark matter evidence was found. But it's spelled "Bullet" on APOD and other places. Just wondering.

Okay, here's where I admit a secret that bites me periodically. I have dyslexia, and sometimes I just read things wrong in really funny ways. I'm not sure how many times I read Bullet as Ballet, but it was a bunch, and it was just know that I realized that Bullet is not the same as Ballet when you had them side by side.

Yes, I should have said Bullet. I just read it wrong a lot of times. Thanks for the excellent catch.

StarStryder
2006-Oct-12, 03:12 AM
Hum,
...she may have subconsciously spotted (for example) a tutu, during Frasers interview.

I now have an image of Fraser wearing a tutu skirt over normal cloths behind his mic...

[shaking head clear]

Nah - I just thought that light bending around galaxies was more of a ballet move than a bullet-like thing to do.

StarStryder
2006-Oct-12, 03:23 AM
I have a couple of questions for Pamela Day from the Dark Matter Podcast:
1) Why do you refer to gravity bending light? Doesn't gravity warp space and light just travel along this warped space? Is this type of conceptual shortcut possibly responsible for our lack of understanding of what is going on with dark matter/energy?

There are two schools of thought. One says that space is actually curved by mass and the light is going in a straight line through curved space. The other says that space is not actually curved, but gravity bends the light in a way that is observationally identical to curved space. I went with the "it's an analogy" school of thought. Since these are observationally identical schools of thought, I don't really have a hard and fast personal view, and I've found that most people understand the gravity bends light idea better, and understanding was my goal.

[QUOUTE]
2) You mentioned that the outer objects of galaxies and clusters are moving faster than expected, more like a rigid platter, rather than slowing down. I assume this slowing down is what we observe in spiral galaxies. Rather than additional dark matter, could there be an interaction between matter that we can only observe at this scale?[/QUOTE]

The idea behind Modified Newtonian Dynamics is that gravitational interactions are different at really large distances. I'm actually going to refer you to a good review page rather than try and explain stuff here. Check out The MOND Pages (http://www.astro.umd.edu/~ssm/mond/)

Nereid
2006-Oct-12, 07:44 AM
There is a BAUT Q&A thread devoted to DM (http://www.bautforum.com/showthread.php?t=42223) (well, at least the observational basis of it ....).

OK, OK, it's not complete; I will write another section soon, ... promise ... :o

Oh, and the MOND pages? Just keep in mind, as you read the material therein, that it's highly partisan ... (an apparent example (http://www.bautforum.com/showpost.php?p=823074&postcount=215)).

Blob
2006-Oct-12, 11:03 AM
I recall seeing something about friction-produced static electricity in the earliest moments of the big-bang being required to initiate the accumulations of mass that have culminated in the large-scale structures of the universe.

Hum,
Big Bang nucleosynthesis (http://en.wikipedia.org/wiki/Big_bang_nucleosynthesis) and the production of Sterile Neutrinos?

emarksmi
2006-Oct-15, 05:04 AM
Dark Matter (and Dark Energy) have always mystified me. While this PodCast didn't really clear anything up, it at least showed that there are a lot of very smart people who are just as confused as I am.

To be honest, I kind of view Dark Matter and Dark Energy as modern day Ether. We see things we don't truly uderstand so we theorize that there must be something there to make such and such happen. I wouldn't be surprised if we turned out to be completely incorrect and that Dark Matter and Dark Energy are simply aspects of the laws of Physics that we simply don't understand yet.

Still, I enjoy following the research, even if I don't understand it all.

eremon
2006-Oct-15, 10:48 PM
I recall seeing something about friction-produced static electricity in the earliest moments of the big-bang being required to initiate the accumulations of mass that have culminated in the large-scale structures of the universe.

Hum,
Big Bang nucleosynthesis (http://en.wikipedia.org/wiki/Big_bang_nucleosynthesis) and the production of Sterile Neutrinos?
I think the idea was that something other than classical gravity is required to effect the minuscule initial agglomerations of particles that eventuated in objects large enough to exert gravitational influence. Friction between densely packed moving particles would have electrostatically produced the necessary attractive force.

In googling I came across these:
Gravity as the second order relativistic manifestation of electrostatic force (http://arxiv.org/ftp/physics/papers/0505/0505194.pdf).
Quantum Cosmology With Decreasing Gravity (http://www.rostra.dk/louis/quant_01.htm).

Blob
2006-Oct-16, 12:01 AM
Hum,
i think the danger in applying that theory to the earliest moments of the big-bang is that they don't work.
(ie, simply, the earliest moments of the bigbang were filled with radiation (rather than particles) and before say 3000 years the particles were basically thoroughly mixed by that radiation, which would not allow the small `seeds` to form the large scale structures.)
However, computer simulations that use a mixture of cold and hot darkmatter have proved surprisingly successful in replicating the structures we see.

Nereid
2006-Oct-16, 12:01 AM
I think the idea was that something other than classical gravity is required to effect the minuscule initial agglomerations of particles that eventuated in objects large enough to exert gravitational influence. Friction between densely packed moving particles would have electrostatically produced the necessary attractive force.

In googling I came across these:
Gravity as the second order relativistic manifestation of electrostatic force (http://arxiv.org/ftp/physics/papers/0505/0505194.pdf).
Quantum Cosmology With Decreasing Gravity (http://www.rostra.dk/louis/quant_01.htm).I think we can safely say both of these are well and truly 'against the mainstream'!

If any BAUT member wishes to present either of these, and defend them, please start a new thread in our ATM section (http://www.bautforum.com/forumdisplay.php?f=17).

eremon
2006-Oct-16, 12:38 AM
Hum,
i think the danger in applying that theory to the earliest moments of the big-bang is that they don't work.
(ie, simply, the earliest moments of the bigbang were filled with radiation (rather than particles) and before say 3000 years the particles were basically thoroughly mixed by that radiation, which would not allow the small `seeds` to form the large scale structures.).
Perhaps not in the earliest moments. As radiation difuses and atoms condense, would their individual gravity be sufficient to produce aggregation, or could the more locally intense electrostatic forces produced by friction be instrumental?

Aside from that, perhaps the gravitational effects of larger irregularities in the early soup might produce initial clumping. But then, do these irregularities themselves reflect some sort of clumping?

Hum,
However, computer simulations that use a mixture of cold and hot darkmatter have proved surprisingly successful in replicating the structures we see.
I'm interested in the parameters these simulations use to represent cold and hot darkmatter. Can you illucidate a bit on this, or, failing that, provide a reference?

Blob
2006-Oct-16, 01:44 AM
Aside from that, perhaps the gravitational effects of larger irregularities in the early soup might produce initial clumping. But then, do these irregularities themselves reflect some sort of clumping?

Hum,
yeah, there would be large residual irregularities (fossil remnants from inflation, or chance etc) in the hot early universe that would produce clumping - however they alone do not have enough time to form the first blackholes/stars/galaxies/large scale structures that we observe.



Can you illucidate a bit on this, or, failing that, provide a reference?

Millennium Run (http://www.devhardware.com/c/a/Computer-Systems/Millennium-Run-Simulating-the-Universe/), Simulating the Universe

eremon
2006-Oct-16, 02:56 AM
Hum,
yeah, there would be large residual irregularities (fossil remnants from inflation, or chance etc) in the hot early universe that would produce clumping - however they alone do not have enough time to form the first blackholes/stars/galaxies/large scale structures that we observe.

Millennium Run (http://www.devhardware.com/c/a/Computer-Systems/Millennium-Run-Simulating-the-Universe/), Simulating the Universe
From the Millenium Run simulation:

The mass points are roughly a billion times the size of our sun, and ... are just for simulation purposes, trying to add proportionate gravity to areas of the universe where there are stellar objects.
Sounds like this simulation isn't scaled to the more primitive stage where electrostatic forces might have been a factor, perhaps evolving into the "fossil remnants" you mention. Maybe the question is, do the earliest irregularities correllate with clumping of stuff, or are they already present prior to primal nucleosynthesis. I'd propose that all irregularities—whether observed or deduced—fall within the province of science.

Mind you, I'm only serving as the devil's advocate in this discussion. I really don't have a position.

Blob
2006-Oct-16, 12:14 PM
Hum,
the simulations have to be predloaded with irregularities (one of the biggest problems of the inflation model used to be that it smoothed out everything, not allowing anything to form), and begins about 10 million years after the big bang. I'm not a computer scientist but i image that they tried various different ingredients and proportions to produce totally alien universes too.

The fossil remnants, BTW, were the tiny quantum fluctuations, when the universe was the size of a turtle, that are blown up during rapid inflation.

There are computer images at Redshift z=18.3 (t = 0.21 Gyr) HERE (http://www.mpa-garching.mpg.de/galform/press/)


Title: The Origin of the Large-Scale Structure in the Universe: Theoretical and Statistical Aspects
Authors: YEINZON RODR´IGUEZ GARC´IA

We review some theoretical and statistical aspects of the origin of the large-scale structure in the Universe, in view of the two most widely known and accepted scenarios: the inflaton scenario (primordial curvature perturbation ζ generated by the quantum fluctuations of the light scalar field φ that drives inflation, named the inflation), and the curvaton scenario (σ generated by the quantum fluctuations of a weakly coupled light scalar field s that does not drive inflation, named the curvaton). Among the theoretical aspects, we point out the impossibility of having a low inflationary energy scale in the simplest curvaton model.
A couple of modifications to the simplest setup are explored, corresponding to the implementation of a second (thermal) inflationary period whose end makes the curvaton field ‘heavy’, triggering either its oscillations or immediate decay. Low scale inflation is then possible to attain with H* (the Hubble parameter a few Hubble times after horizon exit) being as low as 1 TeV. Among the statistical aspects, we study the bispectrum Bζ(k1, k2, k3) of ζ whose normalisation fNL gives information about the level of non-gaussianity in the primordial curvature perturbation. In connection with fNL, several conserved and/or gauge invariant quantities described as the second-order curvature perturbation have been given in the literature. We review each of these quantities showing how to interpret one in terms of the others, and analyse the respective expected fNL in both the inflaton and the curvaton scenarios as well as in other less known models for the generation of primordial perturbations and/or non-gaussianities. The dN formalism turns out to be a powerful technique to compute fNL in multi-component slow-roll inflation, as the knowledge of the evolution of some family of unperturbed universes is the only requirement. We present for the first time this formalism and apply it to selected examples.

Read more (http://arxiv.org/PS_cache/astro-ph/pdf/0507/0507701.pdf) (306kb, PDF)

eremon
2006-Oct-16, 03:20 PM
Hum,
The fossil remnants, BTW, were the tiny quantum fluctuations, when the universe was the size of a turtle, that are blown up during rapid inflation.

So indeed it is as the little old lady said—"turtles all the way down!"

SingleDad
2006-Nov-18, 01:53 AM
First off my daughter and I love you pod casts :D

We love to listen, and then think over ideas for ourselves. It's a way for me to keep my daughter interested in science and that's always good. This Dark Matter stuff has been a lot of fun. My daughter wanted me to ask a question.

Has anyone ever thought that maybe "space" has mass (using my words) and that gravity is the surface tension of space? and that space isn't the "void" we though, but is make of something and this something like water has like heavy water?

Again that was mostly my works and mostly her idea. She's only 8 and I'm not a rocket scientist, so go east on the flames :D

Brian

Fraser
2006-Nov-18, 03:23 AM
Thanks for your feedback Brian, we really appreciate it. Regarding your daughter's theories, she'll need to get some funding and write a paper or two. ;-)

SingleDad
2006-Nov-18, 04:17 AM
Well, as far as funding and writing a paper. It would be hard to have her accepted by the community, when her paper is crayon and marks :razz: as well the funding will get spent on toys :do:

We'll continue to listen to you casts, debate them, and entertain you guys with our finds :dance:

Brian

Blob
2006-Nov-18, 04:34 AM
Has anyone ever thought that maybe "space" has mass and that gravity is the surface tension of space?

Hum,
it is an interesting idea.
But, recent discoveries have shown that dark matter can clump up (not into small clumps) so space cannot have mass.
However, just this week the Hubble space telescope has discovered that dark energy has been around for most of the universes history. It is basically the opposite of mass; Space is acting like an sort of anti gravity that is expanding the universe.

As for gravity being the surface tension of space, tell her she knows too much; this is cutting edge science that the best brains in the world are working on right now (ie, M-theory and loop quantum gravity).

SingleDad
2006-Nov-18, 05:01 AM
Oh my goodness!! if I laugh any harder I'll wake her up. She's a very smart child (tested 120 IQ in 1st Grade). I just want to keep her on the right road. Maybe we'll can entertain you guys at the same time =p

luckynate
2007-Jan-03, 02:03 AM
Hi Fraser....

Recently I had a conversation with the very well known cosmotoligist, Russ Croman. He pitched the Question to him
"What is Dark Matter" He promptly replied to me....
"That's a Good Question!" and went on to say, "Nobody Knows!"

I have posted my question about it many times and I never receive
any replies! This is my theory about the unknown......

I happen to believe in INFINITY! Infinity is primarally has two major componets: Endlessness and Timelyness, no beginning and no ending to either! There never has been a moment, when infinity was not existing! Why is it so difficult to believe that infinity does not have COLOR?? In other words, at night when we point our eyes away from Earth towards the sky and focus on the "Dark Matter" between any form of light, (stars,planets,etc.)
and believe the "Darkness" is the color of Infinity...BLACK!

The idea that the "Big Bang" theory that supossedly started the beginning of the Universe is absurd! What was existing before the Big Bang!?? Common sence tells us there had to be Something!
If nothing else, there had to be infinity and Temporature!
Note: the absence of heat, temporature will Drop! I don't think we know how far down temporature can drop?

Much more, but it is after 4am and I'm ending here!

Regards,
Gary / searlesgold
g-man=coin@sbcglobal.net

First off...if space and time were infinite, then light would have had an infinite amount of time to reach us before now (even across infinite space). This would mean that every line of sight in the night sky would end on a star, and the whole sky would be as bright as the sun, EVEN AT NIGHT!

Secondly, black is NOT a color, but rather a lack thereof, which means that when something looks black, it is not giving off ANY visible light.The "empty space" you speak of is not in fact empty at all, but rather filled with microwave radiation, which is a form of light, our eyes just can't see it.
This microwave radiation that you refer to as BLACK is in fact the MAIN evidence that we have to support the big bang theory that you dislike so.

Third, your notion of something existing BEFORE the big bang is completely unfounded. Time had it's beginning at the BIG BANG. It was the FIRST thing that happened, so there was no such thing as BEFORE the big bang. This also directly refutes your statement about time having no end, because the beginning is already one end, and the other end may be just around the corner.....or not....so what common "sence" were you basing this statement on?

NOTE: the lowest temperature is called ABSOLUTE ZERO...that is how low the temperature can drop....no lower. that's the limit.period.


thanks for reading,
LUCKYNATE

GeorgeX
2007-Jan-13, 02:30 AM
:question: Isn´t it possible that dark energy is just a relativistic effect? All the cosmic backgroud is redshifted to 3K doesn´t that mean that it is moving away from us with relativistic speed? So it´s mass should have grown to an almost infinite ammount. Couldn´t that be responsible for an increasing expansion speed?

Nereid
2007-Jan-13, 01:18 PM
:question: Isn´t it possible that dark energy is just a relativistic effect? All the cosmic backgroud is redshifted to 3K doesn´t that mean that it is moving away from us with relativistic speed? So it´s mass should have grown to an almost infinite ammount. Couldn´t that be responsible for an increasing expansion speed?In a word, no, it is not possible.

First, the expanding universe - as evidenced by the Hubble relationship - fits a relativity-based cosmology well (it's called the Big Bang theory) ... so dark energy (DE) is something 'extra', that's not already in the model.

Second, relativity doesn't work the way you summarised here ... there are some theads in BAUT's Q&A section on this topic - why not go take a look there?

And last, welcome to BAUT, GeorgeX! ;)

GeorgeX
2007-Jan-15, 07:33 AM
In a word, no, it is not possible.

First, the expanding universe - as evidenced by the Hubble relationship - fits a relativity-based cosmology well (it's called the Big Bang theory) ... so dark energy (DE) is something 'extra', that's not already in the model.

Second, relativity doesn't work the way you summarised here ... there are some theads in BAUT's Q&A section on this topic - why not go take a look there?

And last, welcome to BAUT, GeorgeX! ;)

so, now you gave it to me:sad:
1st why not Q&A: I can´t find my own shoes in there, how shall I find an answer?
Where is the mistake? There is a radiation from out there - there should be some matter(I´m beaming-so I am) - it is moving at almost the speed of light(just interrupt me when I´m going astray!)- so the mass of that matter should have increased to a quite large ammount, shall it not?- why could that
not create a gravitational force tearing the universe apart. One awnser could be that the microwave background is too far away, but I didn´t hear that.
So how does relativity work? Feel free to be a bit more specific or at least show me some entrys in the Q&A that explain a thing.

mstul
2007-Jan-15, 07:10 PM
People who say there is dark matter have gone blind looking at the sun trying to find more matter. They say it forms a halo around anything near the mass of a black hole but dont want to admit that it may be the effects of the blackhole at the center of the precieved dark matter.

Most things that we see and measure are atoms that reflect light - Einstein gravity.
Black holes are made of quarks or chrushed quarks and we cannot assume that large dense quark balls called black holes can display the same precieved effects of gravity that atoms produce - MoND gravity. (I dont believe in singularities)
The spacetime at the center of our sun is propped up by the light that it produces and we see that light because it can still escape.

I think that anything that looks like it has dark matter around it, is the effects of something that does not allow light to escape, since blackholes are NOT comprised of atoms they give the 5:1 gravitational effect in area instead of a 1:1 like the sun and earth

I think that the change in spacetime expansion rates around and inside the "dark matter" of a black hole distorts the light from anything outside our galaxy. If we look out our "dark matter" through into the "dark matter" of another galaxy this would be like looking through the wrong end of a refracting telescope. an example would bet the story where they say andromeda is 5 times larger then we thought it was, or how they have noticed that the Large and Small Magellanic Clouds are moving faster then previously thought.