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Theory Posits Early Stars Powered By Dark Matter

kdawson posted more than 6 years ago | from the here-there-be-winps dept.

Space 115

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.

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Your tax dollars funded this, but no article (-1, Troll)

Anonymous Coward | more than 6 years ago | (#22482854)

I'm guessing that Physical Review hasn't opened up their website for free viewing of articles by citizens who bankroll the research. (abstracts != the whole article)

Re:Your tax dollars funded this, but no article (5, Informative)

red_pete (677686) | more than 6 years ago | (#22483176)

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

Re:Your tax dollars funded this, but no article (0, Troll)

Quadraginta (902985) | more than 6 years ago | (#22483276)

Oh that's right, because Physical Review is edited and typeset by elves, who don't need a salary, so WTF is the journal insisting on an income for? Wretched selfish antisocial bastards.

Re:Your tax dollars funded this, but no article (2, Funny)

moderatorrater (1095745) | more than 6 years ago | (#22483460)

Physical Review is edited and typeset by elves
And that's just the beginning. Care to see how far down the rabbit hole goes?

more of the rabbit hole (0)

Sanat (702) | more than 6 years ago | (#22484062)

Eventually this will begin to show that the "Big Bang" did not start it all to begin.

As the astronomers equipment gets better, so it will be that science will have to change the reasons behind what it is seeing. Look for postulates of dark energy/matter (multidimensional areas in space), and also postulates of light changing its speed from place to place, depending upon the formula around localized reality, especially the time frame.

This will create new insight as how the Universe is moving.

As we approach the speed of Light then our Time frame changes... this also works in reverse... as time frames change then so does the speed of Light. Some locales in space have different time than that of Earth and therefore the speed of Light is also different.

Re:more of the rabbit hole (1)

somersault (912633) | more than 6 years ago | (#22484734)

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 more efficient way to do it just via observation, taking into account for example that if the speed of light in there is veeeeery slow, how are you going to be able to tell? Actually I guess you could see patterns of stars around the edges that have since moved/changed intensity or something, but can still be seen by looking through the frame? Or are the chances of an area with an incredibly slow speed of light not very high?

Actually I just got a little excited there thinking about if the speed of light was faster, you'd be able to see things happen before you normally would, if there was a frame that accelerated the speed of light. I guess the practical upsides to learning all of this could be something like 'subspace' in Star Trek, allowing us to have faster than earth-light travel and communication?

Re:Your tax dollars funded this, but no article (-1)

Anonymous Coward | more than 6 years ago | (#22484108)

Just goes to prove that evolution is false. The Lord will smite the heathen into the lake of fire. Repent and put your faith in Lord Jesus Christ and you may be saved. - http://www.youtube.com/VenomFangX [youtube.com]

Light from nothing? (0, Offtopic)

code_08 (1203684) | more than 6 years ago | (#22482870)

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

Re:Light from nothing? (2, Insightful)

4D6963 (933028) | more than 6 years ago | (#22482988)

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.

Re:Light from nothing? (3, Informative)

MikeDX (560598) | more than 6 years ago | (#22483284)

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

Re:Light from nothing? (1)

Rudi G (1155281) | more than 6 years ago | (#22483906)

transparent = colourless?

Re:Light from nothing? (4, Funny)

thrillseeker (518224) | more than 6 years ago | (#22484018)

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? (5, Funny)

SlashWombat (1227578) | more than 6 years ago | (#22483288)

Dark matter stars make BLACK LIGHT?

Re:Light from nothing? (1)

Jugalator (259273) | more than 6 years ago | (#22483352)

How can something so dark create so much light...
I'm not sure the article even say they would be shining much.

Dark Stars? (2, Funny)

ArcherB (796902) | more than 6 years ago | (#22482876)

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

Re:Dark Stars? (1)

calebt3 (1098475) | more than 6 years ago | (#22483616)

"Dark Star" and "Dark Energy" didn't sound ominous enough. That's why they were quickly phased out in favor of "Death Star" and the "Dark Side of the Force"

I cannot believe... (1)

Roadkills-R-Us (122219) | more than 5 years ago | (#22491918)

...that the Dark Side created the universe.

Overstates? (5, Interesting)

moderatorrater (1095745) | more than 6 years ago | (#22482898)

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? (4, Informative)

John Hasler (414242) | more than 6 years ago | (#22482944)

> 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:Overstates? (1, Interesting)

mark-t (151149) | more than 6 years ago | (#22482952)

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

Re:Overstates? (1)

moderatorrater (1095745) | more than 6 years ago | (#22483016)

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.

Re:Overstates? (1, Interesting)

mark-t (151149) | more than 6 years ago | (#22483156)

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.

Re:Overstates? (1)

eclectic4 (665330) | more than 6 years ago | (#22483622)

"...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.

Speak for yourself. (1)

das_schmitt (936797) | more than 6 years ago | (#22483634)

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.

In other words, "Math is hard, let's go shopping."

Re:Speak for yourself. (1)

emilper (826945) | more than 5 years ago | (#22485922)

In other words, "Math is hard, let's go shopping."

How about: "These particular results of the use of Math do not really make sense, and we cannot really verify/falsify them. It's fun, but right now I have to do some shopping, so I'll go build a bridge or do something for which I can get paid, and with the money I get I'll buy that second-hand Cray you saw yesterday and we'll be back in the business of discovering particles that are so small that, if Heisenberg was right, we can't know much about them but a product of their speed and of their mass, or back in the business of counting the number of angels that can dance on the head of a pin, if you fancy that more."

Re:Overstates? (2, Interesting)

Sanat (702) | more than 6 years ago | (#22484166)

"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.

Also now science is seeing that the Galaxies in space are rotating in a manner that also defies their calculations. A galaxy rotates all together nor like our planets whizzing at different speeds causing retrogrades and etc.

There is much to discover and we live at the opportune time to assist in these understandings of how the universe is really designed. We have chosen the perfect time to be here on Earth!

Re:Overstates? (2, Informative)

techno-vampire (666512) | more than 6 years ago | (#22484428)

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? (1)

Nazlfrag (1035012) | more than 5 years ago | (#22486916)

I think he was alluding to the fact that there is a new fundamental force in action that makes gravity insignificant at those scales. In other words, why are we so certain dark matter is responsible, and not some fundamental force such as the MOND premise.

Re:Overstates? (0)

Anonymous Coward | more than 6 years ago | (#22484602)

The universe wasn't designed, we didn't choose to be here at any given time, let alone now, and the speed of light is indeed constant throughout the universe. And you are a kook.

Re:Overstates? (1)

ceoyoyo (59147) | more than 5 years ago | (#22489764)

MOND isn't a serious contender because it still requires dark matter. So if you don't like the AMOUNT of dark matter, you might favour MOND. If you don't like dark matter at all, then it's not going to save you.

Re:Overstates? (4, Funny)

_KiTA_ (241027) | more than 6 years ago | (#22483084)

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:Overstates? (2, Insightful)

mark-t (151149) | more than 6 years ago | (#22483214)

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.

Re:Overstates? (1)

gardyloo (512791) | more than 6 years ago | (#22483266)

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?

Re:Overstates? (2, Insightful)

mark-t (151149) | more than 6 years ago | (#22483504)

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

Re:Overstates? (1)

gardyloo (512791) | more than 6 years ago | (#22483924)

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 effects, or if there is some fundamental, many-to-one mapping to four-space in which calculations *have* to be done (which extra coordinates might qualify as new dimensions).

Re:Overstates? (1)

Lehk228 (705449) | more than 6 years ago | (#22484682)

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

Re:Overstates? (1)

Shinmizu (725298) | more than 5 years ago | (#22490264)

Yes, you can get a hyperdrive for your flying car. You do have a flying car, correct?

Re:Overstates? (1)

Ambitwistor (1041236) | more than 6 years ago | (#22485316)

Just the time dimension. You're proposing extra spatial dimensins, which is not something that "we had already accepted". String theorists like extra dimensions, but there's no evidence of them, and string theorists aren't the whole physics community. Plus, not even string theorists have managed to do what you insist is "radically simple": produce a dark matter equivalent using only the structure of higher-dimensional spacetime. Believe me, if string theory had a simple, workable alternative to dark matter, string theorists would be shouting it from the rooftops.

The usual way in which string theorists incorporate dark matter is to come up with a string vibrational mode that simulates ... you guessed it ... a new kind of invisible particle. In other words, string theory gives more candidates for dark matter.

There are probably brane solutions too, but you can think of branes as dark matter as well ... albeit not matter made of particles.

Re:Overstates? (1)

TubeSteak (669689) | more than 6 years ago | (#22483796)

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"?

Re:Overstates? (1)

mark-t (151149) | more than 6 years ago | (#22484148)

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.

Re:Overstates? (1)

TheSpoom (715771) | more than 6 years ago | (#22484380)

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

Re:Overstates? (1)

techno-vampire (666512) | more than 6 years ago | (#22484478)

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.

Re:Overstates? (1)

dryeo (100693) | more than 6 years ago | (#22484934)

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? (1)

Ambitwistor (1041236) | more than 6 years ago | (#22485274)

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.
We don't really observe non-uniform expansion ... we do see random inhomogeneities left over in the current distribution of cosmic background radiation and galaxies, thought to be partly due to inflation and partly to dark matter.

Adding higher dimensions isn't going to explain that unless you postulate randomly lumpy extra dimensions; otherwise, smooth extra dimensions aren't going to project down to something random in lower dimensions.

And it's not just the expansion of space that you have to explain. It's also the orbits of stars in galaxies, and numerous other observations.

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.
Easy for you to say. Why don't you try actually writing down a higher dimensional field theory which can explain observations of the cosmic background radiation, early universe structure formation, galactic rotation curves, galactic cluster interactions, galaxy collisions like the Bullet Cluster, etc.?

I think you will find that what you get is not "simple" (if you get anything at all, which I doubt), and almost certainly not simpler than just postulating the existence of a new kind of particle (several types of which have are already suggested from existing paricle theories for independent reasons).

And how is inventing invisible extra dimensions so superior to inventing invisible extra particles, anyway?

Re:Overstates? (5, Interesting)

shma (863063) | more than 6 years ago | (#22483260)

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:Overstates? (-1, Troll)

Anonymous Coward | more than 6 years ago | (#22483928)

... who's ...
Are you literate? Just asking.

And no, Neptune didn't explain anything. The orbital perturbations are still not sufficiently explained. Neptune and Pluto/Charon aren't big enough. They were in the right place in the sky when someone was looking, but something else is out there.

Re:Overstates? (1)

deglr6328 (150198) | more than 6 years ago | (#22484642)

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

Re:Overstates? (1)

Ambitwistor (1041236) | more than 6 years ago | (#22485334)

I like the Neptune-Mercury analogy a lot and use it myself.

Another analogy for dark matter is the neutrino: it was an invisible, virtually non-interacting particle introduced purely to maintain the internal consistency of the known laws of physics (the conservation laws). It was 12 years before they were actually discovered, since they interact so weakly. Dark matter also interacts weakly, but is thought to be much more massive than a neutrino, so it's difficult to produce in a particle accelerator.

Dark Matter is a good concept, but (1)

anandsr (148302) | more than 5 years ago | (#22486378)

for the fact that MOND gives good results.

There is nothing wrong with Dark Matter(DM) as a concept. It is certainly possible that DM exists. The only problem with DM (at least at the Galactic scale) is that MOND gives very good results. Its like the Max Planck's corpuscular theory of Black Body Radiation. Planck assumed that radiation could only have some allowed energy levels. This assumption was able to fit the Black Body Radiation curve very well. This is how Quantum theory was born.

Now MOND is similar in nature. It is based on an assumption that at a certain acceleration level gravitational pull no longer drops at r^2 with distance, but drops at r with distance. It is actually defined as a geometric mean of the acceleration due to Newtonian gravity and the special acceleration level. This simple modification works very well at the Galactic level.

DM at galactic scale would be perfectly fine if we did not have MOND work so well.

The other fact is that MOND does not work well beyond galactic scale. I believe that both approaches could be true. MOND and DM can both be true. I suspect that DM could be spread out nearly uniformly. The density might not be sufficient to produce much gravitational effect at galactic scales, but at larger scales, it may produce a large observable effect.

MOND can be explained very easily by GR, if the universe is curved. The problem is that flatness is considered a settled question.

Re:Overstates? (2, Informative)

Btarlinian (922732) | more than 6 years ago | (#22483306)

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:Overstates? (1)

mdenham (747985) | more than 6 years ago | (#22483456)

Out of curiosity, is the radiation-to-normal-matter ratio about the same as the supposed dark-energy-to-dark-matter ratio? If it is, wouldn't the simplest explanation of dark energy be that it's the equivalent of light for dark matter?

That's as logical as God (0, Flamebait)

EmbeddedJanitor (597831) | more than 6 years ago | (#22483676)

To paraphrase: "We can't think of any other alternatives so this one must be true!". Gee that's a scientific approach!

Re:That's as logical as God (1)

moderatorrater (1095745) | more than 6 years ago | (#22483836)

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

What? (1)

jgoemat (565882) | more than 5 years ago | (#22486306)

Considering that the need for Dark Energy to explain the expansion of the universe is in question [slashdot.org] , I don't know. We know very little about Dark Matter and Dark Energy. Now we hear that our own galaxy might be twice as thick [usyd.edu.au] as we previously thought. Dark Energy and Dark Matter are added to observed data to come up with models [wikipedia.org] to explain observations. I'm thinking if 75% of the energy in the model is no longer required to explain observations and the 4% of free hydrogen and helium might be doubled that maybe we should take a look at the 25% that is Dark Matter as well.

Re:Overstates? (1)

Xelios (822510) | more than 5 years ago | (#22487288)

IANAP, but our understanding of gravity isn't complete. We have a fairly good understanding of how it operates, but we're not sure what it even is. We assume the effects of gravity remain the same throughout the universe, and throughout time. We assume it works on very large scales much like it does on smaller scales. We have no idea how it works on quantum scales.

With all these uncertainties I think it's jumping the gun to assume any gravitational effects we can't explain with our models of the universe are due to invisible matter, for which the only real evidence are those gravitational effects.

Re:Overstates? (1)

damncrackmonkey (1075919) | more than 5 years ago | (#22488192)

Of course, if you just re-solve the General Relativity equations using the data that's been collected in the last 100 years, it appears that dark matter may be completely unnecessary. This was previously discussed here [slashdot.org] .

Thanks, kdawson (5, Funny)

NereusRen (811533) | more than 6 years ago | (#22482920)

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 (2, Funny)

pha7boy (1242512) | more than 6 years ago | (#22482994)

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.

Re:sure they were (0)

Anonymous Coward | more than 6 years ago | (#22483196)

Dark Matter is just science slang for "god did it..." I have it on authority that Jesus was black, so it makes sense. Given that Ronald Reagan was in fact the devil, and if the government isn't lying about 9/11 then I don't know who is - I'm pretty sure that I am correct in this extrapolation.

Guess what! (1)

EmbeddedJanitor (597831) | more than 6 years ago | (#22483252)

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

Re:Guess what! (1)

dimeglio (456244) | more than 6 years ago | (#22484058)

So if I understand all this, it would appear that dark matter came out of grey matter.

I had this idea that if you take the early universe, place it in a top loading washer and set the dial to spin, then press start, wouldn't you get accelerating expansion? I just Googled this an apparently it's an old idea. Of course, you need a extra-dimensional washer but I'll leave string/brane theory to explain all this. Fits in well with bubble/suds universes too.

Re:sure they were (0)

Anonymous Coward | more than 6 years ago | (#22483992)

Can't get a date? You've accumulated too much dark matter around your waist line.

Re:sure they were (1)

Nephrite (82592) | more than 5 years ago | (#22487344)

Well, essentially they are right. You should just understand the word "matter" in the sense "affair" not "stuff".

Maybe a better word (1)

cthulu_mt (1124113) | more than 6 years ago | (#22483004)

Maybe a better word/phrase for this would be "interesting idea being bandied about".

Its use of "theory" like this that give the mouth breathers down in Florida and excuse.

Re:Maybe a better word (1)

kithrup (778358) | more than 6 years ago | (#22483050)

The correct word is "hypothesis." Until it gets tested, and then it can be a theory.

(Obviously, we need a commercial-length, musical, animated short that explains how a hypothesis becomes a theory.)

Re:Maybe a better word (5, Funny)

dgatwood (11270) | more than 6 years ago | (#22483316)

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:Maybe a better word (1)

Hucko (998827) | more than 6 years ago | (#22483694)

Not bad! Made me laugh.

Re:Maybe a better word (1)

cthulu_mt (1124113) | more than 6 years ago | (#22484568)

Comedy.Gold.

Re:Maybe a better word (1)

Belial6 (794905) | more than 6 years ago | (#22483304)

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

I figured this out several years ago... (4, Funny)

3waygeek (58990) | more than 6 years ago | (#22483042)

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.

Re:I figured this out several years ago... (1)

sirmonkey (1056544) | more than 6 years ago | (#22485058)

aaaa-haha ha hah a hah a ha ooo man that just made my year, seriously.

Very Very Dark Matter (0, Redundant)

christurkel (520220) | more than 6 years ago | (#22483072)

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

Re: Very Very Dark Matter (4, Informative)

Dice (109560) | more than 6 years ago | (#22483330)

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 (0)

Anonymous Coward | more than 5 years ago | (#22487196)

"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."

If that were confirmed, it would be a serious problem for current dark matter theories as well

Re: Very Very Dark Matter (5, Informative)

lgw (121541) | more than 6 years ago | (#22483744)

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: Very Very Dark Matter (0)

Anonymous Coward | more than 6 years ago | (#22484460)

You obviously haven't eaten at Joe Bob's diner.

Re: Very Very Dark Matter (0)

Anonymous Coward | more than 5 years ago | (#22485822)

Oh well, dark matter is just a ordinary piece of matter that happens to reflect not enough radiation to be observable. Tike every planet in a different solar system. It does not have some strange properties, it is just simple dirt that is very far away.

Michigan researchers (0, Flamebait)

phrostie (121428) | more than 6 years ago | (#22483172)

Michigan researchers are using the same theory to come up with democratic delegates.
similar research is going on in florida

Re:Michigan researchers (-1, Troll)

Anonymous Coward | more than 6 years ago | (#22483208)

fuck michigan!

Are they still stars? (2, Interesting)

smackenzie (912024) | more than 6 years ago | (#22483228)

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:Are they still stars? (1)

Jugalator (259273) | more than 6 years ago | (#22483318)

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:Are they still stars? (1)

Jugalator (259273) | more than 6 years ago | (#22483370)

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.

Re:Are they still stars? (1)

John Hasler (414242) | more than 6 years ago | (#22483478)

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

Re:Are they still stars? (1)

Idiot with a gun (1081749) | more than 6 years ago | (#22483374)

But it's stated that they consumed each other before nuclear fusion could start. Wouldn't this make them more like short lived dark dwarfs?

Re:Are they still stars? (0)

Anonymous Coward | more than 6 years ago | (#22483914)

I'm just guessing here, but the way I see it from the article, these things aren't completely dark matter. If they were, it would be more like a cloud of free streaming particles since dark matter particles annihilate if they run into each other (generating a lot of other stuff), and this happens very rarely, so they can't support hydrostatic pressure which is how a star usually avoids collapsing. It's more like a cloud of hydrogen and dark matter, but instead of hydrogen fusion keeping the star hot and preventing gravitational collapse, it is dark matter particle annihilation which releases the great majority of energy that keeps the star hot (the star naturally cools by radiating light). Still you need the hydrostatic pressure from the hydrogen ball to support itself. Since these objects would share many of the same qualities of what we currently call stars, and since there is probably a continuum between regular stars, and these old stars, it's more convenient to call them a class of stars than something different.

Re:Are they still stars? (1)

kmac06 (608921) | more than 6 years ago | (#22484312)

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.

Re:Are they still stars? (1)

ceoyoyo (59147) | more than 5 years ago | (#22489936)

According to Pumba, a star is a giant ball of flaming hot gas.

Dark matter stars are made of the same stuff as regular stars (hydrogen and helium) except they have a bunch of dark matter in them too, that may have interesting effects.

You wouldn't call the sun not-a-star because it also has heavier elements than helium in it, would you?

Dark matter is an optimization? (5, Interesting)

BLAG-blast (302533) | more than 6 years ago | (#22483258)

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:Dark matter is an optimization? (2, Interesting)

Anonymous Coward | more than 6 years ago | (#22483566)

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.

Re:Dark matter is an optimization? (2, Interesting)

Planesdragon (210349) | more than 6 years ago | (#22483674)

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.

Re:Dark matter is an optimization? (1)

Rich0 (548339) | more than 5 years ago | (#22488418)

The irony of this of course is that the universe could really be only 6000 years old or whatever under this model. I mean, when you play an RPG and you read some book in the game referring to a battle that took place 500 years prior, that doesn't mean that the game is 500 years old...

For all you know the universe was created this morning and you just think you remember everything prior.

My Farts are Powered by Dark Matter... (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22483432)

...I believe this is consistent with String Theory, as I had spaghetti for dinner, last night...

vaudeville killed the minstrel show star (1)

tverbeek (457094) | more than 6 years ago | (#22484390)

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

Star Power (1)

HTH NE1 (675604) | more than 5 years ago | (#22490904)

You mean it wasn't pennywhistles and moonpies?

She was raped 37 times and (0, Troll)

FakEbay (1242688) | more than 6 years ago | (#22484616)

FUCK EBAY

Rule for Future Dark Matter Posts (0)

Anonymous Coward | more than 6 years ago | (#22484800)

Id like to propose a new Slashdot rule for all future articles pertaining to Dark Matter and/or Dark Energy.

Unless you are a particle physicist or an engineering physicist or a PROFESSIONAL astronomer (amateurs, sorry youre out), then you are no longer allowed to comment on these articles.

The fact of the matter is, NONE of you (except maybe 2 or 3) have any idea what youre talking about. The editor is quite correct in this post in saying that the theory isnt 100% proven yet, and as a few posters have been kind enough to point out, that IS enough to not throw out the theory completely. So there are two sides to this, but you cant take a side on an argument if you don't even know what the argument is about. So...the rest of you...just stop talking

Re:Rule for Future Dark Matter Posts (1)

alzoron (210577) | more than 5 years ago | (#22486298)

The singularity is about to explode!

Speculation is not a theory (1)

JeffLass (1174007) | more than 5 years ago | (#22487018)

The proposed idea that early stars were made of dark matter, etc. is pure speculation. Speculation is NOT a theory. Let's review: scientifically speaking "a theory is a systematic and formalized expression of all previous observations, and is predictive, logical, and testable" [wikipedia]. A theory also is built on a substantial mathematical/physical/chemical foundation on which it rests. Unfortunately there is an air-headed defintion that 'theory' is a speculative conjecture, opinion, or untestable notion; but only numbskulls think along those lines. Also, dark matter and dark energy are in themselves nothing more than speculative conjectures ... there is currently NO theory of dark matter nor of dark energy. In time, a workable theory involving them will no doubt be built.

Just how weakly... (1)

DriveDog (822962) | more than 5 years ago | (#22487672)

How weakly do Weakly Interacting Massive Particles interact? Now we have them colliding and annihilating themselves? Often enough to create enough pressure to offset the gravity trying to pull the "star" together? Just how wimpy are your WIMPs?

And I also am not convinced these hypothetical objects should be called "stars." Quark stars and neutron stars were at least formerly fusion-powered stars before losing their morals and becoming degenerate matter.

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