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.

Dark Stars?

[ArcherB (796902)]

Maybe that's where all that Dark Energy came from.

Overstates?

[moderatorrater (1095745)]

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.

Re:Overstates?

[John Hasler (414242)]

> 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:

[mark-t (151149)]

Or, perhaps, modifications to theory regarding the nature of space itself.

Re:

[moderatorrater (1095745)]

Outside of string theory and MOND, what is there that's a serious contender? There are fringe theories, and they could be correct, but that doesn't change the fact that there's a lot of certainty out there for dark matter.

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[mark-t (151149)]

Of course... but then there's at least as much certainty that there's a heck of a lot about the universe we don't know anyways... in other words, it's actually a rather useless theory, except to the extent that I suppose it makes scientists feel better because it makes their existing theories still work without being forced to confront the possibility that we really don't have a clue about anything.

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[eclectic4 (665330)]

"...forced to confront the possibility that we really don't have a clue about anything."

Really? Not one clue, about anything? I think that would be presumptuous in the other extreme.

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[Sanat (702)]

"makes their existing theories still work without being forced to confront the possibility that we really don't have a clue about anything."

Most of the theory right now revolves around our solar system and what occurs there. We have a whole set of formulas to calculate it.

But those formulas fall apart when applied to the very small such as an atom so we make exceptions.

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

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[techno-vampire (666512)]

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.

Re:Overstates?

[_KiTA_ (241027)]

Or, perhaps, modifications to theory regarding the nature of space itself.

But why muck up a perfectly good theory based on observation of reality? Seems counterproductive to me.

Re:

[mark-t (151149)]

Actually, it seems to me that the universe expanding completely uniformly in higher dimensions than what is visible would still explain all of the non-uniform expansion that dark matter was apparently invented to explain. It baffles me as to why they would invent the notion of something invisible to explain anomalous observations instead of going with a no less workable and radically simpler theory.

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[gardyloo (512791)]

Actually, it seems to me that the universe expanding completely uniformly in higher dimensions than what is visible would still explain all of the non-uniform expansion that dark matter was apparently invented to explain. It baffles me as to why they would invent the notion of something invisible to explain anomalous observations instead of going with a no less workable and radically simpler theory.

Something like... higher dimensions?

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[mark-t (151149)]

We had already accepted that there were more than 3 dimensions anyways.

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[gardyloo (512791)]

So far as I know, only time is sufficiently convolved with our "regular" three spatial dimensions so as to be considered another (via Lorentz transforms). Higher dimensionality is invoked all the -- ahem -- time, but these are generally things like Hilbert spaces, of infinite dimensionality.

Hyperspace coordinates are eminently helpful in, e.g., nuclear theory, but there are mappings from these to 4-space, and I am unaware if anyone thinks that the transformations are merely convenient ways to separate out e

Re:

[Lehk228 (705449)]

ok when did i miss the news that we have hyperspace technology, also, where can i get a hyperdrive for my car?

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[TubeSteak (669689)]

Actually, it seems to me that the universe expanding completely uniformly in higher dimensions than what is visible would still explain all of the non-uniform expansion that dark matter was apparently invented to explain. It baffles me as to why they would invent the notion of something invisible to explain anomalous observations instead of going with a no less workable and radically simpler theory.

How do you test for "the universe expanding completely uniformly in higher dimensions"?

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[mark-t (151149)]

Well, as long as the observations don't actually contradict it, it's a working theory. If or when somebody manages to convert Dark Energy into another form of energy, it will be disproved.

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[TheSpoom (715771)]

I feel like if I inserted some Perl code here or something equally indecipherable, I too would get some mod points. Alas, lazy.

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[techno-vampire (666512)]

You have no idea how good it feels to see that I'm not the only one who suspects that Dark Matter and Dark Energy are just ad hoc inventions to make an old theory explain new facts. Personally, I think that when we understand what's happening, we'll find no need for either.

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[dryeo (100693)]

I think you are getting mixed up between dark matter and dark energy.
Dark energy has been invented to explain why the expansion of the Universe is speeding up.
Dark matter is to explain why galaxies stay together without having enough observable mass.

Re:Overstates?

[shma (863063)]

Other alternatives being explored generally rely on alternatives to General Relativity (for instance, TeVeS) to describe results that are attributed to dark matter. I was actually at a day of seminars at the Perimeter Institute last fall where Katherine Freese gave a talk on this subject. The next speaker was actually talking about alternatives to GR and offered an interesting analogy. Early on, when astronomers were still mapping out the solar system, they noticed that Uranus' orbit did not conform to what was predicted by Newtonian gravity. As a result, they predicted a 'dark' body farther out who's orbit was influencing Uranus. This turned out to be Neptune. On the other hand, the precession of the perihelion of Mercury, which was also believed initially to have been caused by an unseen planet (which they called Vulcan), was found to be the result of the failure of Newtonian gravity, and is now seen as confirmation of General Relativity. He concluded that both avenues of enquiry are valid and should both be followed.

Re:

[deglr6328 (150198)]

Is it true that a result at the KATRIN spectrometer showing a neutrino mass of 1eV kills TeVeS once and for all?

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[Btarlinian (922732)]

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:

[moderatorrater (1095745)]

Yeah, now if only they had observed dark matter, that would be a real breakthrough.

Thanks, kdawson

[NereusRen (811533)]

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.

Aside from the actual topic, I want to say that I was pleasantly surprised to see the summary correcting for the improper journalism of the article. Overzealous interpretation of scientific results by journalists is a common complaint around here, and our editors who know that (and can easily recognize it when they review the submission) are the perfect ones to catch the inaccuracy and notify us in advance, so we aren't mislead about the actual claims of the scientific paper. Thanks, kdawson, for the excellent editorial addition to this story.

sure they were

[pha7boy (1242512)]

everything is explained by dark matter. Universe heavier then we think it should be? dark matter. can't figure out the big bang? dark matter. I bet soon enought someone will figure out a way to tie dark matter to the cables in the middle east that got cut the other day.

Guess what!

[EmbeddedJanitor (597831)]

... and where did the dark matter come from? Well it was created from normal matter by running time backwards.

I figured this out several years ago...

[3waygeek (58990)]

after all:
1. Nibblonian civilization [wikipedia.org] predates the Big Bang by 17 years.
2. Nibblonians poop dark matter.

Ergo, the first stars were made of Nibblonian poop.

Are they still stars?

[smackenzie (912024)]

Don't we have a pretty concrete definition of what a "star" is? If these early objects were actually composited of dark matter, wouldn't they be something else?

For example, a tennis ball and a "tennis-ball-shaped" object made of iron are two very different objects. I know which one I would like to have hit me in the head.

Re:

[Jugalator (259273)]

If these early objects were actually composited of dark matter, wouldn't they be something else?

Not if the dark matter would collect into clumps of matter through gravity to kickstart fusion reactions and turn it into balls of plasma.

Re:

[Jugalator (259273)]

Ah, I see I missed the part in the article saying fusion reactions would maybe not start. Hmm, yes then, I also think it would be borderline to actually call them stars? After all, brown dwarves are called "failed" stars, because they never get the fusion reactions going due to too low mass.

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[John Hasler (414242)]

But they did generate energy through reactions between the dark matter particles. Seems to me that this makes them a variety of star.

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[kmac06 (608921)]

Well pretty much anything that's big enough is a star once it's formed. It just so happens that any known object is formed mostly of hydrogen.

Dark matter is an optimization?

[BLAG-blast (302533)]

If this was a simulation, would you simulate very atom? Or would you bulk compute matter that was less important, until it became important then simulate every atom?

Could dark matter, or matter we have trouble seeing, be the equivalent of hiding polygons which don't need to be rendered in a 3D scene?

Geez, I hope not. Quick, prove me wrong.

Re:

[by Anonymous Coward]

More like a bad simulation.

You can't get your galaxies to meet project specs, so you fudge your algorithm and hope the teacher doesn't notice.

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[Planesdragon (210349)]

Geez, I hope not. Quick, prove me wrong.

Ok. If we were a simulation, and were simulating only the important stuff, that simulation would include the appearance of particles far off in the light-cone. To our PoV, it'd be as if they were actually always simulated.

vaudeville killed the minstrel show star

[tverbeek (457094)]

The dark matter worn on the faces of early minstrel stars was certainly key to their star power.

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[4D6963 (933028)]

How can something so dark create so much light...

First off, dark matter isn't dark but transparent. Then, how could say methane and oxygen which are transparent create light when burning together? Oh I know! Maybe that's because it's not the matter that releases light/energy but its transformation.

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[MikeDX (560598)]

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

Re:Light from nothing?

[thrillseeker (518224)]

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

Didn't see it coming?

Re:Light from nothing?

[SlashWombat (1227578)]

Dark matter stars make BLACK LIGHT?

Re:

[Jugalator (259273)]

How can something so dark create so much light...

I'm not sure the article even say they would be shining much.

Re:Your tax dollars funded this, but no article

[red_pete (677686)]

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

Re:

[moderatorrater (1095745)]

Physical Review is edited and typeset by elves

And that's just the beginning. Care to see how far down the rabbit hole goes?

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[somersault (912633)]

Not that it really matters, because our perceptions will also be different in those places :P I suppose if the frames are localised then that's one way of being able to measure the differences though, rather than just theorising.. possibly by sending an atomic clock in, retrieve it, and see how much difference in time had elapsed? Though if the journey is long then the speed at which the clock is moving would also change how fast it 'ticks', or warp time around it, whatever you want to say. Or is there a mo

Re:

[Belial6 (794905)]

I'm still confused as to why some people think they are smarter because they have clear nasal passages.

Re:Maybe a better word

[dgatwood (11270)]

PC Guy: Hi, I'm a hypothesis.

Mac Guy: And I'm a theory.

PC Guy: Wait a second, how did you become a theory all of a sudden? What, you think you're special now?

Mac Guy: No, it's not that, P.C. I just got promoted because so many new people like me.

PC Guy: So because a lot of people like you...

Mac Guy: Well, and it also helps that I've been subject to a lot of scrutiny and they've concluded I'm not full of holes...

PC Guy: I resemble that remark....

Mac Guy: I know you do, P.C. And, of course, a preponderance of evidence confirms my correctness and robustness. That's one more reason that they made me a theory.

PC Guy: Preponderance of evidence... kind of like the O.J. Civil Trial, then?

Mac Guy: ...

PC Guy: ...

Mac Guy: Okay, I'm just going to have to go with "yes" and we'll call that your best hypothesis....

[Apple logo]

Re:

[Hucko (998827)]

Not bad! Made me laugh.

Re: Very Very Dark Matter

[Dice (109560)]

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 (121541)]

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.