Theory Posits Early Stars Powered By Dark Matter

ethericalzen writes "A BBC article highlights a theory that the first stars may have been powered by dark matter. A group of US scientists published a paper in Physical Review Letters speculating that, unlike the stars of today, which are powered by nuclear fusion, early stars might have been powered by the abundant dark matter crowding the universe after the Big Bang. The theory suggests that these stars would have collided and destroyed one another before nuclear fusion had a chance take hold." The BBC perhaps overstates the certainty with which the dark-matter theory is held, and doesn't mention that the postulated properties of such particles are completely speculative.

Re:Overstates?

[John Hasler]

> How do you overstate the certainty of dark matter? Last I read, the only serious
> alternatives were that there's more interstellar dust than we thought...

That doesn't work because you can't get the observed distribution with baryonic matter.

Re:Your tax dollars funded this, but no article

[red_pete]

Here's the LANL preprint: http://arxiv.org/abs/0802.1724v2 [arxiv.org]

Re:Light from nothing?

[MikeDX]

Actually.. methane and oxygen are colourless... My physics teacher practically beat us to death with that one.

Re:Overstates?

[Btarlinian]

How do you overstate the certainty of dark matter? Last I read, the only serious alternatives were that there's more interstellar dust than we thought (improbable considering the observations of the bending of light), modifications to the theory of gravity (few supporters, unlikely, especially with said observations), and string theory.

I think kdawson meant that they were overstating the certainty of this theory, not the existence of dark matter in general. To be honest, I'm not sure why there are so many people (at least on /.) who want to relegate dark matter the the mathematical physics bin along with string theory. There's plenty of evidence for it. We've even observed gravitational lensing from dark matter. Dark energy [wikipedia.org] on the other hand, may be something of a luminiferous aether [wikipedia.org].

Re: Very Very Dark Matter

[Dice]

That's not accurate, there is much evidence supporting the idea of massive particles which do not interact via the electromagnetic, strong, or weak forces. There is, for instance, the observation of lensing in the Bullet Cluster [nasa.gov] last year which put to rest many of the modified gravity theories. There is also the recent observation reported earlier on /. [slashdot.org] of a galaxy composed of stars whose motion can be described without dark matter. The latter observation is particularly damning, if the effect were due to a misunderstanding on our part of the gravitational force or some quantum mechanical property of normal matter then it should be seen everywhere.

Re: Very Very Dark Matter

[lgw]

There is zero evidence of Dark Matter. Circumstantial but it's just like string theory: a lot of take, no proof.

There's as much evidence for dark matter as there is for black holes or neutron stars or anything else in cosmology that we can't actually visit.

Dark Matter was just one hypothesis among many for why galaxy rotation wasn't as expected until we started getting the very precise measurements of the cosmic microwave background radiation a couple of years ago. That made it clear that the matter mass of the early universe was about 80% non-baryonic, reacting to gravity but not light pressure. The percentage and distribution was predicted well by a dark matter theory, and it has explained some later observations as well.

Re:Overstates?

[techno-vampire]

Each planet rotates a given speed based upon its distance from the sun, yet electrons do not follow that same calculation around the proton.

And that, of course, is for a very good reason: the electrons aren't in orbit around the nucleus in the same way that the Earth is in orbit around the Sun. If they were, electro-magnetic attraction would pull them into direct contact almost instantly.