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Black Hole Information Loss Paradox Solution Proposed
Anuborn Satirak writes to tell us that Physicists from Case Western Reserve University claim to have cracked the black hole information loss paradox that has puzzled physicists for the past 40 years. "The physicists are quick to assure astronomers and astrophysicists that what is observed in gravity pulling masses together still holds true, but what is controversial about the new finding is that 'from an external viewer's point it takes an infinite amount of time to form an event horizon and that the clock for the objects falling into the black hole appears to slow down to zero,' said Krauss, director of Case's Center for Education and Research in Cosmology."
Here's the preprint.
I came here for a good argument
Anyone know what happened to Hawking's proposal for information loss?
o n_paradox
Basically what Hawking said (in a late essay entry in a science conference) was that Black Holes do 'digest' information and therefore you have information loss, however (and this is where his proposal was a bit controversial) Hawking suggested that the conglomeration of parallel universes will have a particular Black Hole present in one, and the same Black Hole missing in another, therefore the TOTAL information for ALL Universes, is retained.
Here's a link to Hawking's Black Hole Paradox: http://en.wikipedia.org/wiki/Black_hole_informati
And from the wiki article, here's the line I'm mentioning in my post:
"...On October 28, 2006, The Discovery Channel aired a show called "The Hawking Paradox". The show explained Hawking's conclusion that one must look at the universe as a whole, and that information lost in black holes is saved in parallel universes where no black holes exist."
It seems that this new solution is completely disregarding Hawking's proposal and replacing it with a new, stretched solution.
A black cat crossing your path signifies that the animal is going somewhere. -- Groucho Marx
Firstly, they emphasize in their paper that they are considering their problem from the point of view of an external observer, rather than the point of view of an observer falling into the black hole. They write: They also contrast their results with previously accepted analysis of black hole formation: So, in essence, they are presenting findings that suggest that even quantum effects are taken into account, the collapse takes an infinite amount of time. This is signficant because it means that while the collapsing mass can appear to get closer and closer to being a singularity, it can never really achieve this final state to an external observer. How this relates to information loss is then described: So, in essence, the collapse of the black hole takes an infinite amount of time, during which time the black hole will evaporate via Hawking radiation. So objects falling into a black hole will never actually be swallowed up into the black hole (though they will get arbitrarily close and arbitrarily crushed!). Since the collapse is never really complete, information about the objects is never entirely lost. The emitted radiation will thus contain 'information' about the infalling objects. This in some way can be seen to resolve the seeming information paradox, whereby black holes were seemingly able to 'swallow up' information and completely destroy it (whereas no other process in the universe appeared able to do so).
There is an article about this same thing in new scientistb lack-holes-really-exist.html
http://space.newscientist.com/article/dn12089-do-
It quotes 't Hooft as claiming that "The process he describes can in no way produce enough radiation to make a black hole disappear as quickly as he is suggesting." So I am skeptical.
we haven't (seen any black holes). You can't "see" a black hole (that's why they're named as they are). We have observed the effects of things which match our expectation of the effects a black hole would cause. I assume the authors of this paper explain how their black-hole-like-object-which-isn't-a-black-hole can cause the same effects.
"National Security is the chief cause of national insecurity." - Celine's First Law
No. Black holes aren't lopsided
Well, IINAP, but I think it's more like the actual hole part doesn't exist until the *end* of the universe.
A black hole is not a thing that exists in time and space, it's an event or process that is a warping the space-time fabric. It's a fine point, but it bears repeating -- a black hole is not a 'thing' that warps time-space, it *is* a warping of time-space. An object actually moving to the center of the black hole takes an infinitely long time to get there, so when it actually does get there, it happens to arrive right at the end of the universe.
So it kind of is like the black hole is perpetually in creation phase, but the matter doesn't disappear until the end of the universe. I read a post a few years back that the word for black hole in Russian is 'Collapsar'. Like a Pulsar always 'pulses', matter is always ( literally *always*, or, from now until the end of time ) collapsing in a Collapsar.
Computers are useless. They can only give you answers.
-- Pablo Picasso
That's a rather zen question, actually. In some ways it amounts to asking "What's the difference between the matter that forms the black hole, and the matter that is falling into it?" Conventionally, the answer would be: all the matter inside the event horizon is part of the black hole, and everything outside the event horizon is falling into it (or, rather, is being gravitationally attracted towards it, and may or may not actually fall).
If this new bit of theory is correct, then the answer actually becomes harder, because the event horizon never forms, so you can't really say that some matter is inside vs. outside. Of course there is probably a sensible way to define a "pseudo-horizon" based upon a threshold where the probability of light escaping sharply drops towards 0.
I guess another way of thinking about it would be to say that this hypothetical matter that is "at the center of where the black hole is forming" would inevitably be included into the collapsing mass and would thus, itself, become part of the black hole.
It's true that EMR that enters the event horizon cannot escape. The evaporation process, called Hawking radiation, is a quantum effect that has no conventional analogue. Basically, in quantum mechanics (or rather quantum field theory), it is predicted that "virtual particles" randomly appear and disappear all the time. These virtual particles actually carry the force of things like the electric fields, magnetic fields, gravitational fields, etc. (they also avoid 'action at a distance' problems...). So in the vacuum, you will get random particle-antiparticle pairs appearing at random, and annihilating each other a moment later (these constant fluctuations are very important in modern theories, actually). If you imagine one of these random fluctuations occurring right beside an event horizon, you can imagine that one of the two particles gets sucked into the event horizon, but the other one escapes and sails off into the universe. The particle entering the black hole will actually reduce its mass (not increase it, as one would normally expect... though the proof of this requires digging into the math quite a bit), and the particle that escapes thereby carries away some of the mass of the black hole. Thus, over time, the blackhole is basically emitting radiation and slowly 'evaporating.'
Now, I know this idea of "virtual particles" randomly appearing and disappearing sounds totally bizarre. In fact it sounds like pseudo-science or an overcomlicated story that particle physicists are weaving. However these effects do have experimental backing (e.g. Casimir forces).
It turns out the rate of evaporation increases as you decrease in size. So really "micro black holes" (it is predicted that they will be created in upcoming particle accelerators) will evaporate very quickly. Big black holes will evaporate slowly at first, but then faster and faster as they shrink, until they get very small and release the last of their energy, in some sort of burst, yes. However a fundamental, unanswered, question is whether the radiation being emitted by the black hole contains 'information' about the states of things that went into the black hole. No one knows for sure. The conventional answer was that any information that goes into a black hole is lost forever.
However to many scientists, this answer was unsatisfactory.