Accelerating universe and dark matter

[Forsmann]

Musical meditations over interesting pointless matters a few years ago

 

After a long session I came up with an idea that if something was present before the big bang, this could be the dark matter.

Therefore it would be of a different origin, and above the gravity laws of the universe.

Dark matter could be like a canvas where the universe is the painting.

 

Theory 1

 

Dark matter= Picture yourself a gigantic sphere of air with gravitational force from the equator of the perimeter all around.

Big bang = Imagine a small firecracker set of inside this gigantic sphere.

Accelerating universe=There was not any big bang in the sense of a detonation.

The gravitational force from the outer perimeters of the sphere is the real cause of the expansion.

 

Don´t really like the first one. Seems to lack some sort of purpose.

This one is better:

Theory 2

 

Darkmatter= Imagine the water in a huge calm lake.

The known universe = Imagine an explosive divice set off inside the huge lake.

There is no accelerating explosion in the lake.

As the water is influenced by winds and other factors, what we observe here is merely a movement of "the water"(dark matter).

 

Nowdays I rarely have time for this kind of thinking, but maybe it can trig the imagination of others.

 

Cordially

J.Forsman

[eoinmac]

these are hard for me to imagine, it seems like you're talking about the existence of other dimensions yet undetected influencing our universe? I've read some interesting stuff saying that dark matter might not even exist and there are other reasons for the gravitational effects. One theory is that our universe is on the surface or inside of a gigantic black hole and the gravity from it is what we mistake as dark energy and dark matter and that is also why the universe is expanding. not a physics expert but still find this subject intriguing!

[Butters]

I see Dark Matter and Energy as basically place holders for gaps in our understanding. Dark Energy is the explanation for the increasing acceleration between galaxies, as I (very basically) understand it. It's also possible that we simply do not understand the effect of gravity over very large distances, or when involving very large masses and it actually has a repulsive effect.

 

Dark Matter is also just an invention to cover why galaxies spin in the way that they do and hold together as they do (again, very basic understanding on my part) but there could be a variety of reasons why this may happen which we simply haven't observed yet. I believe that we will soon come to explain these 'dark' areas of our knowledge with one or perhaps several explanations for each...

[hewj11]

Does dark matter bend space time by its mass but doesn't interact with matter,but its gravity clumps ordinary matter to make galaxies?

[layman77]

I wonder, are we sure that dark matter exists? It's proposed because there is a greater gravitational pull then the "light matter" would allow. But, what if it isn't dark matter, matter we can't see in this universe. What if the gravity comes from some other universe, dimension, where their matter interacts with ours?

[Butters]

We aren't at all sure that dark matter exists. Consider the theory of the celestial spheres. They described the movement of the heavens very precisely by postulating the existence of an element called quinetessence that made a series of spheres encircling the earth. They contained all the celestial bodies embedded within them. Because these models could be used to quite accurately predict the movement of planets they seemed a reasonable explanation. There was a slight problem caused by the fact that the orbits were spherical and not elliptical, but the theory seemed at least as plausible as dark matter and dark energy seem now.

 

In my opinion, dark matter and dark energy are analogous to this theory and will be superceded once we have more information.

Edited August 10, 2010 by Butters

[Martin]

Does dark matter bend space time by its mass but doesn't interact with matter,but its gravity clumps ordinary matter to make galaxies?

 

Yes. You say several things here---all correct as far as I know.

 

AFAICS dark energy (the estimated 75%) is much more of a puzzle than dark matter (the 20%). The two are extremely different, as I suspect you realize, and you are talking just about dark matter.

In my experience when people talk as if they think dark matter is somehow dubious or mysterious, they are usually relying on out-of-date information or on pop-sci media like "discovery channel".

 

One can see and make maps of the concentration of DM around clusters of galaxies, using the "weak lensing" effect.

Maps of DM concentration can then be compared and correlated with what one can see has happened to the clusters and what is currently observable. So astronomers have a pretty good handle on DM.

Another good perspective is to google "Smoot TED". You get a 20 minute talk by Nobel laureate George Smoot where he shows movies of computer reconstructions of the collapse and condensation of DM in the early universe. The formation of cobwebby patterns and voids, as the stuff fell together. These were calculated using a dynamical model of how DM behaves in an expanding geometric context, under the effect of its own gravity.

Indeed the concentrations of DM would have helped pull together ordinary matter to make clusters of galaxies, as you said.

[hewj11]

Thanks for the reply martin. But the only way to "see/experience" dark matter is through weak lensing. If it doesn't interact with matter then how do we plan on capturing it to run experiments?

 

Dark energy: the cover term for the reason of space expanding. Where to even start with that, creating a theory from little data and ideas.

[TheTheoretician]

Hi, I'm new here but been doing science for ~20 years. I have been working on the ultimate theory and have been able to place dark matter within visible energy. This explains where this missing mass of the Universe is found - within the photons themselves - and also communication faster than the speed of light.

 

Oh, and BTW, this forum wouldn't let me use my nickname, so I reclaim it when I sign out.

 

Peace,

 

Ik

[Airbrush]

If it [dark matter] doesn't interact with matter then how do we plan on capturing it to run experiments?

 

That is something the Large Hadron Collider may help with.

 

I think DM may be gravity from matter "tucked away" in higher dimensions that somehow leaks thru to our spatial dimensions. It can never be detected, unless we could view higher dimensions, maybe the LHC can. Only the effects of it can be measured.

Edited August 18, 2010 by Airbrush