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I was watching Nova (Absolute Zero) the other night and near the end of the show they described this other state of matter as it approaches absolute zero. (Bose-Einstein condensate). I was wondering if it possible that dark matter in the universe could be this Bose-Einstein condensate. Since it would take a very long time for a ball of gas (brown dwarfs or planets that survived) that was collapsed and ran out of fusion or fission fuel to approach such a temperature, it would imply that the age of the universe may be infinite.

Are there any theories about Dark Matter along these lines?

One of the properties of this state of matter is that it apparently slows down light to a crawl and lets light speed up again when it leaves the condensate.
I found interesting to say the least.
cartrite

I watched the same program as well, so I thought I would chime in. I don't think that dark matter would be Bose-Einstein condensate for two reasons.

First it is said that the deepest regions of space are said to be 3K above absolute zero, which is too warm for a Bose-Einstein condensate to appear. However if it was/is, this would have radical repercussions on the real size of the universe, in as such that the actual size would be vastly smaller then it appears by several orders of magnitude. The only way I could see to prove this would be to examine nearby galaxies along warmer regions of space and compare them to other galaxies that have great voids of nothingness. If both galaxies are at equal distance then the light one going though the great void should appear to be in a much younger state of evolution.

The second reason is because with all the photons zooming around at different wavelengths, it would warm up any region of space above the Bose-Einstein condensate level. Although they use lasers of specific wavelengths to remove heat, another laser would destroy the Bose-Einstein condensate, which was why hey had to do all the experiments in the dark.

This is just my interpretation on this, and I could be totally wrong. We are just beginning to understand Bose-Einstein condensates, and will learn much more in the future. At the very least this will help with our understanding of quantum theory.

BTW with Bose-Einstein condensates, would this constitute a 5th state of matter the other being solids, liquid, gas, plasma?

MKruer wrote:BTW with Bose-Einstein condensates, would this constitute a 5th state of matter the other being solids, liquid, gas, plasma?

http://www.chem4kids.com/files/matter_states.html agrees.

Chem4kids wrote:There are five main states of matter. Solids, liquids, gases, plasmas, and Bose-Einstein condensates are all different states of matter

The more-or-less mightly Wikipedia says

Wikipedia wrote:The most familiar examples of states of matter are solids, liquids, gases, and plasmas; the most common state of matter in the visible universe is plasma. Less familiar phases include: quark-gluon plasma; Rydberg matter; Bose-Einstein condensates and fermionic condensates; quantum spin Hall state; degenerate matter; strange matter; superfluids and supersolids; and possibly string-net liquids.

Furthermore, Wikipedia lists the state of matter:

States of matter roughly in order of increasing energy density.

Quantum Hall state
Quantum spin Hall state
Bose-Einstein Condensate
Fermionic Condensate
Superfluid
Supersolid
Solid
Amorphous solid
Crystalline solid
String-net liquid
Liquid
Supercritical fluid
Colloid
Plasma
Degenerate Matter
Electron-Degenerate matter
Neutron-degenerate matter
Strange-matter/quark matter
Quark-gluon plasma
Weakly symmetric matter
Strongly symmetric matter

First it is said that the deepest regions of space are said to be 3K above absolute zero, which is too warm for a Bose-Einstein condensate to appear.

I thought this myself. But to play the Devil's advocate, Do we really know that this is true? We are taking are measurements from 1 place. Kind of like looking out of a fish bowl. A question to ask is , have there been any experiments on microwaves at 3k to see if the microwaves are reflected back by anything like hydrogen gas, plasma, Bose-Einstein condensate, etc.

The second reason is because with all the photons zooming around at different wavelengths, it would warm up any region of space above the Bose-Einstein condensate level.

But there was an experiment that shot a laser through the Bose-Einstein condensate and it seemed to slow down the laser beam and let it speed up again when the beam reached free space. The condensate was still there. They did this in a laboratory that must have been a little above 3k above absolute zero in the surrounding area.

Anyhow, if this condensate were out there in galactic voids, would there be a way to detect it. I suppose that since it slows down light that may cause a redshift.

cartrite

I missed the show (darn!), but I find the question posed very interesting. It immediately brought to my mind this -
Physicists Slow Speed of Light

So, why not the same happening out in space?

You can watch it online at pbs.org. The beginning of clip 10 has the laser experiment. They show actual footage too.
cartrite