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Theory Posits Early Stars Powered By Dark Matter

Posted by kdawson on from the here-there-be-winps dept.

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.

9 of 115 comments (clear)

  1. Overstates? by moderatorrater · · Score: 5, Interesting

    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.

    1. Re:Overstates? by mark-t · · Score: 1, Interesting

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

      --
      File under 'M' for 'Manic ranting'
    2. Re:Overstates? by mark-t · · Score: 1, Interesting

      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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      File under 'M' for 'Manic ranting'
    3. Re:Overstates? by shma · · Score: 5, Interesting

      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.

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      I came here for a good argument
    4. Re:Overstates? by Sanat · · Score: 2, Interesting

      "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!

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      And in the end, the love you take is equal to the love you make
  2. Are they still stars? by smackenzie · · Score: 2, Interesting

    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.

  3. Dark matter is an optimization? by BLAG-blast · · Score: 5, Interesting

    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.

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    M0571y H@rml355.
    1. Re:Dark matter is an optimization? by Anonymous Coward · · Score: 2, Interesting

      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.

    2. Re:Dark matter is an optimization? by Planesdragon · · Score: 2, Interesting

      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.