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Space Science

"Burning Walls" May Stop Black Hole Formation 100

KentuckyFC writes "Black holes are thought to form when a star greater than 4 times the mass of the Sun explodes in a supernova and then collapses. The force of this collapse is so great that no known force can stop it. In less massive stars, the collapse cannot overcome so-called neutron degeneracy, the force that stops neutrons from being squashed together. Now a Russian physicist says another effect may be involved. He points out that quantum chromodynamics predicts that when neutrons are squashed together, matter undergoes a phase transition into "subhadronic" matter. This is very different from ordinary matter. In subhadronic form, space is essentially empty. So the phase change creates a sudden reduction in pressure, forcing any ordinary matter in the star to implode into this new vacuum. The result is a massive increase in temperature of this matter that creates a "burning wall" within the supernova. And it is this burning wall that stops the formation of a black hole, not just the degeneracy pressure of neutrons. This should lead to much greater energies inside a supernova than had been thought possible until now. And that's important because it could explain the formation of high energy gamma ray bursts that have long puzzled astrophysicists."
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"Burning Walls" May Stop Black Hole Formation

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  • by V50 ( 248015 ) * on Monday June 15, 2009 @12:16PM (#28336453) Journal

    I'm sorry, but after reading the title of the article, all I can think about is all that spicy food I ate last night...

  • by Alcimedes ( 398213 ) on Monday June 15, 2009 @12:28PM (#28336625)

    I never like when scientists can't explain a major aspect of something like a black hole. They have models/predictions etc., but there are these little pieces that are missing.

    Then someone comes along with an elegant solution that fits perfectly into the existing theory/model/design and suddenly all these unexplained pieces make perfect sense.

    That is what science is about. Revelation based on fact, not faith. At the end of the day I think it's a lot more rewarding, although a lot harder to come by.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      In other words, he just put forth a possible explanation without any hard data to back it up. People have done the same in the past, only to have the observations go against their hypotheses. Building a hypothesis is only half the battle; you still need to gather evidence to support it.

      • one usually forms a hypothesis to fit data, not the other way around
        • Re: (Score:3, Funny)

          by Chris Burke ( 6130 )

          one usually forms a hypothesis to fit data, not the other way around

          But either way, the second step is always apply for a grant [besse.at]!

        • You mean unlike the dark matter/energy theory, that was created, because the data did not form the hypothesis, but the hypothesis must!!!1!1one(

          • Damn. Please ignore what went trough of my comment, and imagine it would have looked like this:

            You mean unlike the dark matter/energy theory, that was created, because the data did not fit the hypothesis, but the hypothesis must!!!1!1one be true?

            Thank you for your cooperation. And have a nice day. ;)

          • Well, the alternatives to dark matter/energy suck. Either there's more matter and energy out in the universe than we can observe directly, or gravity doesn't work the same on large scales as it does on small scales. Dark energy is hypothesized because we have not observed anything to account for the accelerating expansion of the universe.

            The theories of dark matter and dark energy require the fewest assumptions, and best explain the observed phenomena, so it's they're working theories du jour. We don't like

            • He wasn't criticizing dark matter theory any more than you just did.

              He was pointing out that the statement "hypothesis are usually created to fit the data, not the other way around" was utter non-sense. Ideally, that's true, but we end up with observations that should not exist based on everything else we observe, it's a thorn in the side and it needs an explanation. Thus what are essentially still just hypothesis get called theories because a) observations necessary have so far been impossible and b) the

    • by Mark_in_Brazil ( 537925 ) on Monday June 15, 2009 @01:14PM (#28337199)

      When I was an undergrad, I worked on CASA, the Chicago Air Shower Array. It was a big array of detectors in the Utah desert, designed to identify point souces of ultra-high energy gamma ray bursts and get more information about the showers of particles they create when they hit the atmosphere.

      It's nice to see a model that could conceivably give an idea of how gamma ray bursts happen. In 1988-89, there really weren't any very good candidates. The problem was interesting enough to get James Cronin, who had won a Nobel Prize with Val Fitch for their discovery of a certain kind of symmetry violation in particle physics, interested in experimental astrophysics. He was one of the principal scientists on the project. And he even did some manual labor, like helping with wrapping detectors. I remember him eating the lunch he had brought from home and talking to me about the health benefits of garlic as we worked on preparing detectors one day.

      Each box had four detectors in it, each detector made of a piece of scintillator with a big photomultiplier attached, all wrapped in black to make it light-tight. In addition to an identifying number, the grad students gave each box a name. Some were named for blues musicians, for example. At some point, the undergrads working on the project started expressing creativity by using made-up names to sign the detectors we had prepared and tested. To this day I wonder if Cronin ever saw the one I had signed as "Cronan the Barbarian."

    • However, I have a lot of speculation on any theory especially those about space where we have yet to really explore and travel, where someone assumes a few laws about existence of such an anomaly, and therefor think themselves experts
      on the subject. I tend to think it is a work in progress until we can provide 100% proof that wood floats in water, or ice melts into water, etc....we have no proof of anything concerning black holes, because we don't even have one near us to view and analyze......!

      • "I tend to think it is a work in progress until we can provide 100% proof that wood floats in water, or ice melts into water, etc...."

        Not surprising you think it's "a work in progress", that is what it is supposed to be. Proof is for axiomatic systems. Science offers a way to make usefull predictions of the future with various degrees of certainty, that certainty never reaches 100% as it does in maths (and dare I say religion).

        Sure you can demonstrate a piece of wood floats but that is not "100% proof
    • Re: (Score:2, Insightful)

      by NAR8789 ( 894504 )
      What?! No! The heart of science is not fitting hypotheses to data. That's the sort of dangerous fallacy that produces Aristotle's "science", and in fact what dangerous fundamentalists thrive on. The thing that sets science apart is rigorous, repeatable empirical testing of not previously observed predictions. Not to say that the hypothesis in the article isn't exciting, but the already raising it up as a shining example of scientific triumph starts down a path I find terrifying.
    • That is what science is about. Revelation based on fact, not faith.

      But you realize that faith is not an inherently religious concept. You have faith that science will explain things like the "Big Bang" and the "cause" of gravity. In fact, you have faith that science is a useful tool in the first place. What if all of our observations are based on a lie perpetrated by an all-powerful trickster (see Descartes)? Or perhaps reality is merely a series of shadows projected on a cave wall in front of a captive audience (see Plato). Attempting to set science above religious d

    • That is what science is about. Revelation based on fact, not faith. At the end of the day I think it's a lot more rewarding, although a lot harder to come by.

      Many scientific revalations were based on faith, the assumptions a scientist makes when creating their theory. Unlike blind-faith commonly associated with religion, science allows those faith based assumptions to be tested. Ptolemy created a scientifically valid geo-centric model of the solar system, in that it could accurately predict the motion of

    • Where's the fact? What I see here is "revelation" based on speculation...
  • Quantum chromodynamics, "subhadronic" matter,. .... , I think you got me lost there ;-)
    How can these hypotheses be checked?
    • by PPH ( 736903 )
      Sounds like its time to fund the next earth-eating collider project.
      • build it around the equator!
      • If we ever found a way to accelerate neutrons, that might work. Trouble is, neutrons have no charge, and our colliders need a charge to grab on to. We have neutron sources, in the form of fissioning elements, but there's no way to get those neutrons to go around in a circle. So the usual trick of slamming particles into each other at near-lightspeed isn't possible. I suspect that testing this particular idea won't be possible until we understand so much about particle physics that we don't even need to

        • One could suggest using a gravity powered accelerator, though that might be a tad difficult. However, from what I understand you should be able to use other hadrons to investigate collapse into subhadronic matter, which is precisely what LHC was built to play with.
        • by vlm ( 69642 )

          If we ever found a way to accelerate neutrons, that might work.

          Attach them to some protons and fling the combined nuclei. How bout a 1:1 ratio, good ole deuterium.

          Shouldn't it be possible to see this effect in n-n collisions, much as quark effects were discovered?

          If colliding deuterium ions into bulk deuterium doesn't work, fling the accelerated ions at a target just right to break off the proton and let the neutron fling onwards into a "bucket of neutrons" from a source or a reactor. Reaction rate will be pretty slow, but if you got all day to let it run, thats OK?

        • by osu-neko ( 2604 )
          In a neutron star, of course, it's neutrons undergoing the hypothesized process, but is there any reason why protons wouldn't under the right conditions? If we could observe this happening with any subatomic particles, it would be sufficient to prove this is what happens to matter under those conditions.
    • Re: (Score:3, Funny)

      by donaggie03 ( 769758 )
      Create some subhadronic matter and see if it causes a region of space with lower pressure than the surrounding space. As a bonus, measure the temperature of that space before and after the pressure vacuum stabilizes.
      • Re:wowsa ! (Score:5, Funny)

        by reverseengineer ( 580922 ) on Monday June 15, 2009 @02:16PM (#28338045)

        Create some subhadronic matter and see if it causes a region of space with lower pressure than the surrounding space. As a bonus, measure the temperature of that space before and after the pressure vacuum stabilizes.

        Show all work. Write legibly in #2 pencil or blue or black permanent ink. Do not write on test booklet. Do not start until signaled to do so by your proctor. Destruction of the earth will result in automatic failure. You will have three (3) hours.

      • by jd ( 1658 )

        Ideally, you'd also ensure it had a negative energy density. Then, when it supernovas, you will flood the universe with exotic matter and wormholes.

    • Re: (Score:2, Funny)

      Quantum chromodynamics, "subhadronic" matter,. .... , I think you got me lost there ;-)

      You must be new here.

    • by osu-neko ( 2604 )

      Quantum chromodynamics, "subhadronic" matter,. .... , I think you got me lost there ;-) How can these hypotheses be checked?

      I just checked. There's so such thing as "subhadronic" matter. Wikipedia gives me a "page not found".

  • Comment removed based on user account deletion
  • QCD Phases (Score:4, Informative)

    by Roger W Moore ( 538166 ) on Monday June 15, 2009 @12:37PM (#28336741) Journal
    That's an interesting article. New QCD phases have been postulated for quite a while (colour superconductors etc.) but last time I talked to an expert on it and asked whether it could account for the missing energy in a Supernova (currently SN models seem to fizzle more than explode) his reply was that the phase change was too slow to release enough energy to help the SN go bang. I'll have to read the paper to see it this idea addresses this issue.
  • Supernovae (Score:2, Informative)

    by SteelAngel ( 139767 )

    "Black holes are thought to form when a star greater than 4 times the mass of the Sun explodes in a supernova and then collapses. "

    If a star is greater than _8_ solar masses you get a supernova.

  • Damn those degenerate neutrons!
  • The phrase that stuck out for me was, 'a phase transition into "subhadronic" matter'. While I certainly recognize the need for new vocabulary when a new model/theory/phenomenon is described or discovered, this particular phrase, "subhadronic matter", gives me Star Trek Voyager flashbacks.

    "Captain, the Borg are pulling us in!"

    "Lt. Torres, can you reroute the power to the deflection array dish, and invert the signal to send out a subhadronic matter stream? That should disrupt the tractor beam long enough for

  • Both? (Score:1, Funny)

    by Anonymous Coward

    So now the sky, and the walls are burning?

  • Great! Let's use the scientific method to test this hypothesis. Oh wait, nevermind.

    Sorry, but it's hard not to be cynical about astrophysics. Dark matter sounds like something invented by a writer for a Japanese cartoon series, and the scientific explanation sounds about as likely to be true.

    • Then come up with a better idea of why galaxies move at the same rate on the outer edge that they do towards the center. That is what Dark Matter is all about, I'm not sure what Japanese cartoon series you're talking about but the idea from Dark Matter came from observations.
      • Re: (Score:2, Informative)

        by getnate ( 518090 )
        The scientific method does not require a better theory in order to tear apart an incomplete or wrong theory.
      • The same way dimensions on the quantum scale fold in on themselves, it is possible that space itself is higher dimensional, and we see a subset of the dimensions. Thereby, on a galactic scale, there are more dimensions, which can easily screw the math to make gravity more powerful on a larger scale.
    • Re: (Score:3, Insightful)

      by michaelwv ( 1371157 )
      That's exactly what we will do. This hypothesis will be quantified into making predictions about what we will see from supernovae and gamma-ray bursts (and perhaps other events). We will then plan and conduct observations of these events and see if the predictions of this hypothesis are consistent with the new data. A lot of interesting ideas like this come out but then stall for a while as people try translate qualitative ideas into quantitative predictions. Once that happens we can go out and test the
    • by Yvanhoe ( 564877 )
      The SF explanation : all the missing matter is made of Dyson spheres...
      • by HiThere ( 15173 )

        For some reason that I don't understand it's not supposed to be baryonic matter. I.e., no protons. This rules out the Dyson spheres.

        Sorry. I'd really like that explanation to work.

        • by dissy ( 172727 )

          The SF explanation : all the missing matter is made of Dyson spheres...

          For some reason that I don't understand it's not supposed to be baryonic matter. I.e., no protons. This rules out the Dyson spheres.

          All of the data from our observations is based on the assumption that what we are seeing is not being influenced by an intelligence.

          And you have to admit, if a Dyson sphere could be designed engineered and built, there would probably have to be a little bit of intelligence behind it!

          Yea I know, but it makes for some wonderful sci-fi story lines :D

    • by ae1294 ( 1547521 )

      Sorry, but it's hard not to be cynical about astrophysics. Dark matter sounds like something invented by a writer for Sailor Moon the Japanese cartoon series, and the scientific explanation sounds about as likely to be true.

      Fixed it for you...

    • Dark matter sounds like something invented by a writer for a Japanese cartoon series, and the scientific explanation sounds about as likely to be true.

      Would you prefer they call it "Here-Be-Dragons Matter"?

    • by osu-neko ( 2604 )

      Great! Let's use the scientific method to test this hypothesis. Oh wait, nevermind.

      Sorry, but if you don't understand how to test these hypotheses using the scientific method, you clearly don't understand science well enough to have a clue. What you really mean is, it's hard not to be cynical when you don't have a clue and can't be bothered to get one.

  • They can rest easy knowing that their Fire-Wall, will protect them from a Black Hole too...not just outside intruders!

  • observational tests? (Score:5, Informative)

    by bcrowell ( 177657 ) on Monday June 15, 2009 @02:48PM (#28338447) Homepage

    There are a lot of very difficult theoretical problems involved in trying to describe the structure of neutron stars. The classic picture of a star made of nothing but neutrons is probably not quite right, and is possibly qualitatively wrong in important ways. There's supposed to be an upper limit on the mass of a neutron star, and the theoretical uncertainties get greater as you get closer to this mass limit. E.g., it's possible that you get quark stars. We just don't know, because we don't know the behavior of the strong and weak nuclear forces with sufficient precision to be able to extrapolate to these extreme conditions.

    Given all that uncertainty, which has existed for many decades, it's not at all surprising to me that there's a corresponding uncertainty about the conditions under which a neutron star is or isn't unstable with respect to collapse into a black hole. The paper [arxiv.org], which is linked to from the end of the Technology Review article, is pretty heavy going. My field is nuclear physics, not relativistic astrophysics, and I had a hard time understanding it. The author's English is also pretty hard to understand, so it's hard to tell exactly what he's saying his conclusions are. But if you look at the end, he seems to be suggesting that black holes actually do not form.

    I wonder to what extent existing observations constrain this idea. For instance, we know that the Sagittarius A* object at the center of our galaxy has a mass of at least 3.7 million solar masses and a radius of less than 6.25 light-hours. It would be interesting to know what he proposes this object is, if he says it's not a black hole.

    • Don't what he proposes, but some prefer MECOs (http://arxiv.org/abs/astro-ph/0603746) or Dark Energy Stars (http://arxiv.org/abs/gr-qc/0508115).
    • Sagittarius A* object at the center of our galaxy has a mass of at least 3.7 million solar masses

      What the author is refering to is stellar mass black holes, ie. black holes that form from core collapse in star. The Supermassive black holes such as the one in our galaxy are a different beast entirely.

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