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Space Science

Black Holes Grow By Eating Quantum Foam 164

An anonymous reader writes "The discovery that even the most distant galaxies have supermassive black holes at their cores is a puzzle for astrophysicists. These objects must have formed relatively soon after the Big Bang. But if a galaxy is only a billion years old and contains a black hole that is a billion times more massive than the Sun, how did it get so big, so quickly? Now one cosmologist says he has the answer: black holes feed off the quantum foam that makes up the fabric of spacetime. This foam is 'nourishing' because it contains quantum black holes that can contribute to the black hole's growth. This idea leads to a prediction: that the supermassive black hole at the center of the Milky Way must also be growing in this way and at a rate that we should be able to measure. Just watch out for the burps."
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Black Holes Grow By Eating Quantum Foam

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  • I thought supermassive black holes grew by sucking superstars into them.

  • CERN scientists suggested they might create miniature black holes whilst looking for the Higgs Boson particle. There was some concern of the hypothetical danger creation of such black holes might pose. Now are we positing the first black holes of the universe fed off just such Quantum foam stuff?
    • I'm not sure there are many supermassive black holes in our vicinity, so I think we're probably safe.

    • by geekoid ( 135745 )

      " There was some concern of the hypothetical danger creation of such black holes might pose.
      not my anyone who know WTF they where talking about.

    • Re:Con CERN (Score:4, Interesting)

      by It doesn't come easy ( 695416 ) * on Wednesday September 11, 2013 @05:23PM (#44824387) Journal
      Actually, it kind of fits if you bring all of the intelligent guesswork together. I read somewhere that the tiny tiny tiny black holes (possibly) created by the LHC would evaporate (due to Hawking Radiation) at an exponentially accelerating rate -- the more mass they lost the faster they would loose more, ending in a quantum sized obliterating explosion. If true, and if this new idea is correct as well, that would imply that there is a perfect point where the mass evaporation from Hawking Radiation would *just* equal the mass accumulation from consuming quantum foam. If the black hole mass starts out greater than this point then the black hole grows, less and it shrinks. Someone ought to be able to calculate (roughly?) the magical amount of mass needed to produce a pseudo-stable black hole...
      • Re: (Score:2, Funny)

        by Anonymous Coward

        Why calculate when you can find it experimentally. Think of the fun!

    • Re:Con CERN (Score:5, Interesting)

      by TapeCutter ( 624760 ) on Wednesday September 11, 2013 @06:57PM (#44825009) Journal

      There was some concern of the hypothetical danger creation of such black holes might pose.

      More concerning to me was the uninformed speculation that lead to those concerns. As one physicist quipped here on Slashdot at the time, "You misunderstand what motivates physicists. If the LHC did get sucked up by a mini black hole we would not run from the building in fear, we would run towards it with notebooks at hand".

      • If the LHC did get sucked up by a mini black hole we would not run from the building in fear, we would run towards it with notebooks at hand".

        Only the experimental physicists. The theoretical physicists would ignore the black hole until their equations proved it exists.

    • Doesn't a black hole have to have enough mass that even light can't escape?

      If a massive star can't do this, how would there be really small "mini" black holes?

      Either it can stop light from escaping (therefore it is incredibly massive) or it can't (therefore it is not black).

      If you see my angle here ...
      • It's the mass to size ratio that is relevant here.

        If you manage to compress an object the mass of the Himalayas (i.e. a minuscule mass on an astronomical scale) way down to the size of an elementary particle, you end up with a black hole in your laboratory. Enjoy, but enjoy quick, as the thing will start to eat your laboratory immediately...

        Should you prefer to make a black hole out of Grandpa's old lawn mower instead, just make sure to compress it down to a far, far tinier size than you'd have compressed t

    • by sjames ( 1099 )

      If super massive black holes behaved like raccoons when you leave cat food out, it might become a problem.

  • How you get so big eating food of this kind?

  • I will be glad when they figure out that this is all just one huge (multitrillion year) cycle. Everything will eventually get sucked into the various holes; the larger holes will over power the small holes and suck them in until there is nothing left but one hole that eventually sucks our concept of time in to it until there only exists an extremely small and massively dense blob that reaches critical mass... at which point there is another big "bang" setting the entire process in motion again. Redistribut

    • by boristhespider ( 1678416 ) on Wednesday September 11, 2013 @04:52PM (#44824067)

      Doesn't work - the big bang is not an expansion into pre-existing spacetime. Further, it's very hard to find a way of forcing a black hole solution of GR (Schwarzschild would be the most plausible in this context) to suddenly turn into a cosmological ("Friedmann-Lemaitre-Robertson-Walker") solution of GR. What you *can* do is embed an FLRW solution inside a Schwarzschild and get a model indistinguishable from observation, but extraordinarily contrived, and indeed pointless. (Come to that I'm not fully convinced those models genuinely work because the Schwarzschild solution is static, but if you linked that with Wetterich's recent model where the "expansion" is actually a manifestation of the increasing mass of particles you could avoid that issue, too and, indeed, avoid having to embed an FLRW inside a Schwarzschild at all.)

      But if you refine what you say a bit it's not very far from an idea Penrose proposed a while back but has, unfortunately, never published in detail, although he's put out some (admittedly extremely ill-advised -- Penrose is basically a genius, but knows little of either statistics or observation) papers claiming signatures on the microwave sky. Basically Penrose points out that eventually everything will evaporate to radiation one way or another: if we follow any extension to the standard model we at least open the possibility that fundamental particles can decay, and otherwise ultimately every path every particle will take will inevitably, over an infinite period of time, take it into a black hole. If there are eventually two electrons in the universe and nothing more but radiation, they will themselves inevitably collide, after an unimaginable period, with enough energy to form a black hole (remember in this scenario the electrons are constantly buffeted by radiation of ridiculously high power... even if most of the radiation is at wavelengths of, say 10m, there will be *some* photons at a vast energy and these will interact with the electrons... eventually... and accelerate them to speeds far in excess of those reached on Earth or, indeed, in the Sun). And black holes radiate. So everything becomes radiation. But for reasons that are rather technical, it is impossible within the framework of GR to distinguish between an infinite future bathed in radiation and an infinite *past* bathed in radiation, because time and length scales become rather arbitrary. Which means that through some process Penrose has never explicated - if that's a word - the ultimate future can wrap onto the ultimate past and suddenly there's a new Big Bang.

      There are also other ways of getting cyclic models, which involve a bit more new physics (new scalar fields, or branes hanging near ours, etc.) but a bit less hand-waving. Indeed, there are many ways of getting cyclic universes. But Penrose's struck me as being nearest to your suggestion.

      • Which means that through some process Penrose has never explicated - if that's a word - the ultimate future can wrap onto the ultimate past and suddenly there's a new Big Bang.

        (TIC)

        So there is life after death, see ya all on the rebound.

        What would one use to accelerate fast enough to get out of this time loop?

        • I would certainly agree that we should take a position of extreme scepticism towards Penrose's claims that quantum gravity gives rise to consciousness.

          My contention is that Penrose is one of the greatest general relativists of the mid-late 20th century, and has only been overlooked because Stephen Hawking is in a wheelchair. What I'd judge as Hawking's greatest successes - and they were very great - were in collaboration with Penrose (in the singularity theorems), in collaboration with Ellis (covariant flui

  • If a black whole can grow by eating space time then how could Hawking radiation ever evaporate it? It simply puts the black whole back into the "it breaks entropy" bucket.
    • No, in the simplest case it gives you a population model. What you've said could be crudely mapped onto a foxes hares model to read "If hares can grow by breeding how could foxes ever kill them all?" What we'd end up with is oscillations or balances, depending on the parameters. Personally, I'd suspect that any balance between consumption and evaporation would kick in around roughly the Planck scale but that really is a knee-jerk guess.

  • So they will grow forever until the universe is one giant black hole?

  • Since the entropy of a black hole is proportional to the area of the event horizon, and this is a reflection of the information content of the black hole, is there an issue with the information situation? Does the quantum foam that spontaneously creates these micro black holes inside the event horizon represent information? Or is there an information quandary implicit in this proposal?

  • Yuck! (Score:2, Funny)

    by trongey ( 21550 )

    Quantum foam? They can eat all they want. I tried that stuff once, it was awful.

  • by ATestR ( 1060586 ) on Wednesday September 11, 2013 @05:31PM (#44824471) Homepage

    I'm not up on the details of contemporary physics, but it occurs to me that since the universe is supposed to have been expanding since the big bang, the overall density has decreased during that time. Does space/time and the Quantum Foam also have a density that might affect the rate at which super massive black holes could gobble it? Could conditions in the early universe encourage black hole growth/consolidation more than the current space environment?

    Black hole growth via this method may still occur today, and be measurable in our own and nearby galaxies, but the rate may be so slow that it is hidden by other factors, e.g.: consumption of local stars/gas clouds.

    • by boristhespider ( 1678416 ) on Wednesday September 11, 2013 @05:43PM (#44824625)

      Nice post.

      "it occurs to me that since the universe is supposed to have been expanding since the big bang, the overall density has decreased during that time"

      Yes, absolutely.

      "Does space/time and the Quantum Foam also have a density that might affect the rate at which super massive black holes could gobble it?"

      Yes; one would normally link it to what I guess would be called the Planck density. (We have a Planck energy and a Planck length, which imply a Planck volume, so a Planck density would be the Planck energy / c^2 divided by the Planck volume. Forgive me not going through the algebra but it would probably be a few minutes' work on Wikipedia; the important point is that a fundamental volume associated with the quantum gravitational scale probably exists. Or may exist.)

      "Could conditions in the early universe encourage black hole growth/consolidation more than the current space environment?"

      Certainly. If nothing else, higher energies - and a higher density is immediately a higher energy through E=mc^2 - would most likely lead to a high production of black holes. Maybe not, but what we *can* say is that higher energies leads to a higher abundance of primordial black holes through more standard processes, so that even if the foam black holes are *not* preferentially produced in the extremely early universe, other black holes actually are, so the absorption rate will be higher anyway.

    • it has density and no density at the same time

  • One astrophysicist now claims Black Holes are made by Freaking Magic...

    This comes after NuSTAR found Black Holes "wherever it looked" {my words}, ""We found the black holes serendipitously," explained David Alexander, "We were looking at known targets and spotted the black holes in the background of the images."" anywhere between 0.3 and 11.4 billion light-years from Earth. http://www.sciencedaily.com/releases/2013/09/130909154918.htm [sciencedaily.com]

    NuSTAR http://www.nustar.caltech.edu/ [caltech.edu] and http://www.nasa.gov/mission_pages/nustar/main/index.html#.UjDw25I03n0 [nasa.gov]

    Now it's a race to explain this, and in the lead is Marco Spaans with mini black holes aka "Quantum uctuations in the form" that I would
    tend to think would of made itself more pronounced than just adding substance to a Black Hole.

    • by Tablizer ( 95088 )

      So we have:

      * Dark Energy
      * Dark Matter
      * Dark Gravity
      * Dark Foam
      * Dark Holes
      * Dark Profit!

      "I didn't eat the cake, honey, a Dark Mouth ate it."

  • End of the Universe (Score:5, Interesting)

    by McFortner ( 881162 ) on Wednesday September 11, 2013 @06:45PM (#44824929)
    If black holes grow by the absorbing the quantum foam, then the universe is slowly gaining mass as new matter is spontaneously being generated but not getting a chance to vanish back to where it came from. This means that eventually the cosmic expansion will halt and be reversed. This universe could end not in heat death but a big crunch. We may have the final answer in the ultimate fate of the universe if this theory is correct.
    • FWIW I like your explanation, simple concise, logical.

    • Comment removed based on user account deletion
    • I just had a radical thought.

      It's probably wrong, as it is the product of ignorance. As such nothing that follows should be seen as factual. It is supposition. And again, probably very wrong.

      Still, What if the physical volume of spacetime is far larger than it currently appears, the force driving spacetime expansion is the energy that creates vacuum fluctuations entering the true ground state (as more spacetime that has fewer fluctuations), and the currently observed universe's rate of expansion is an illus

    • by dissy ( 172727 )

      If black holes grow by the absorbing the quantum foam, then the universe is slowly gaining mass as new matter is spontaneously being generated but not getting a chance to vanish back to where it came from.

      The quantum foam is still just a conversion from energy to matter (and normally back to energy again)

      Any mass gained as matter had to come from mass of energy, so the net sum is zero, not gaining.

  • by Anonymous Coward

    This quantum foam is going to go right to my Schwartzchild radius.

    Does this metric make me look supermassive?

  • It doesn't sound like too crazy of an idea to me, that these apparently precocious supermassive black holes were just left over from an earlier universe. Suppose our Big Bang erupted into a preexisting space, and these awaiting black holes significantly accelerated the galaxy-making schedule this time around. Yes, this time around.

    Instead of hyperinflation expanding faster than light in the first microseconds, perhaps our Bang opened into a pre-existing "cavity" of a few light-minutes across. Perhaps we
    • by Anonymous Coward

      Sort of like the ancient Tai Chi Yin-Yang symbol which has a tiny yang white dot in the center of the 'full' black yin part and a tiny black yin dot in the center o the 'full' yang part. Okay, so yes, maybe I did reread those Dancing Wu Li Masters books in the last little bit.

  • It ate one Sun per year for a billion years. Next question?
  • by master_p ( 608214 ) on Thursday September 12, 2013 @02:34AM (#44827459)

    In Physics we learn that energy/matter cannot be created or destroyed, just change form, and that the universe is a closed system where the total energy/matter is static.

    Recently we have also learned that virtual particles are constantly appearing and then disappearing and the void of space is not really a void but a boiling soup of virtual particles. But since these particles disaappear instantly after they appear, the net result is that the universe's energy/matter quantity does not change.

    However, the idea in this article claims the opposite: virtual particles, i.e. the quantum foam, does not disappear, but it is added instead to the energy/matter of the universe, thus making the universe an open system. Isn't that a violation of the known physics laws?

    • When you don't really understand what is going on, you have to make up crazy sounding stuff to make it look right. Until astronomers get a new paradigm shift like Einstein created with space-time we will continue to get crazier and crazier sounding theories. Once someone make a new understanding of what we see out there then all the dark matter and energy and strange acceleration of the universe will go away and be understood in the new physics that we develop as normal observations.
    • I think it really helps to remember that thermodynamics is an *emergent* theory: it's only valid when you're talking about vast numbers of particles. There is nothing, for instance, that stops a few electrons -- even in isolation -- grossly violating the second law of thermodynamics and settling into a state of vanishingly low entropy. Just that, when you look at larger systems they will never, as a system, move to a state of lower entropy.

      Putting it another way, look at the gas bouncing around your room ri

    • by Bengie ( 1121981 )
      "Laws" of nature only happen on average. Given an infinite amount of time, they will always win. The real question, is how does this newly added energy, get removed?
  • As many people have said, the main theory is there are constantly equal amounts of opposite virtual particles being created and destroyed in empty space. There was a theory that along the edge of a black hole, precisely at its event horizon, a pair could get split apart before it can annihilate itself. That always seemed dumb to me because to sit on the very edge of an event horizon, it implies the opposing particle entered the universe with energy to accelerate it to approximately the speed of light in e
  • Quantum foam makes me roam.

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