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Black Holes Don't Trap Information Forever
sciencehabit writes "New calculations suggest that black holes are not a one-way street. Anything that falls into them may eventually come out. The findings lend important support to quantum gravity, but fly in the face of Einsteinian relativity. They also support Stephen Hawking's reluctant admission that information couldn't be destroyed by black holes. Penn State researcher Ahbay Ashtekar was quoted saying, 'Once we realized that the notion of space-time as a continuum is only an approximation of reality, it became clear to us that singularities are merely artifacts of our insistence that space-time should be described as a continuum.' Let the physics infighting begin."
Continua are so much prettier mathematically though. Couldn't quantisation just be an artifact of a closed universe i.e. standing wave modes in a finitely sized continuum ? Quantum theory is so damn *ugly* compared to GR and its extensions (Kaluza-Klein, Einstein-Cartan). Sigh.
I was under the impression that due to the relativistic effects, stuff (photons, matter, information, whatever) wasn't so much destroyed by a black hole as indefinitely delayed, owing to the massive bending of space-time by the singularity. Or do they mean by "eventually" what I mean: it might eventually come out, but the time it takes approaches infinity.
It's interesting they are only just realizing it. Thermodynamic folks have had to deal with a related issue for a long time.
Almost everything interesting in thermo has to do with a phase transitition popping up somewhere.
THe funny thing is this. There are no phase transitions in the real world. THey only occur on paper continuuum models. However there are a lot of things that look awfully like phase transitions so they are useful to think about.
What am I babbling about. Well phase transitions happen at places where infinite derivatives occur in mappings. And that's all fine on paper where you have an infinite number of states. If you think of states as being something like basis vectors then it' like saying you can write a fourier transform of a square edge with a continuum of frequencies.
But since there's only a finite number of states available to any system, you dont have enough basis vectors to describe a discountinuty.
So phase transitions dont' exist technically speaking. There's always some transition zone around the edge of the transition.
I think this is what they are talking about here.
Some drink at the fountain of knowledge. Others just gargle.
I am afraid that we have to say goodbye to one of the great memes of physics, namely, "black holes don't have hair." This statement, we are sure now, is simply incorrect. A black hole is defined by far more that spin, charge and mass.
Mondern Thermodynamics, Information Theory and after a bitter battle event Quantium Mechanics and GR have admited that black holes indeed do have hair. Even Hawkins has given up this battle and admitted he was wrong. (sidenote: It is an interesting story how Hawkins would say he he proved this point in a recent paper. Many physicsts dispute his version of events as it was already obvious which way the wind was blowing and regard Hawkins paper as a refolumation of the results from the work of others in the above sciences - and not even the most useful formulation at that).
As the artical says what goes in to the black hole will eventually escape or to put it in another more correct way, the information concerning the state of the matter and light that once *fell* in to the BH will become available to the universe again at some, possible distant, point in the future.
I have a feeling the meme "black holes don't have hair" is so atractive and addictive we will be living with and debunking it on slashdot for many years to come but lets be very clear, black holes do have hair.