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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.
Black holes, however, are not "hairy" either. That is to say, a black hole can be entirely characterized by its position/velocity/acceleration, mass, charge, and rotation. There is (literally) no other definable characteristic of a black hole besides these things.
To make laws that man cannot, and will not obey, serves to bring all law into contempt.
--E.C. Stanton
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.
bit is the physical unit in question. Landauer's principle shows that forgetting 1 bit = increase in entropy of k ln 2. k in joules per kelvin (entropy) is 1.380 6504(24)x10â'23. ln 2 is 0.693147181. So, 1 bit is "worth" about 9.56993933x10-24 of entropy.
At room temperature of ~ 300K, that corresponds an energy of 2.8709818x10^-21 Joules. We know that 1 kilogram of matter is 8.98755179 Ã-- 10^16 joules by E=mc^2.
So, 1 kilo of stuff existing at room temperature is like the universe knowing 3.13048024x10^37 bits, or 3.55894399x10^24 TebiBytes. One could speculate that that's the storage the simulator running the universe uses for each room-temperature kilo of matter in existence.
Warning: Presence of numbers in scientific notation doesn't mean this post isn't bullshit. Still, the dimensional analysis suggests it's a pretty good estimate.
At least to our present level of understanding, yes. Experience has shown that in hindsight indivisible units aren't.
Help stamp out iliturcy.
size == momentum (incorporated in mass & rotation);
"origin" is not a distinct physical characteristic, especially *if* information cannot be extracted from the black hole;
estimated life-span is likewise not a distinct physical characteristic, but depends on the evaporation rate of the 'hole, which may be obtained from the mass and rotation (which give the mass-to-surface-area ratio simply in the case of no rotation, and more complicatedly in the case of non-zero rotation).
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.
Seems to me that part of the problem is that Newton's basic axioms about space, time, etc., are flawed; and that although Einstein resolved some of the problems, he did not address the basic structure of Newton's one-dimensional notion of time, etc.
If the axioms are different, then the theory is inevitably different. Some of you yonger SlashDotters may not have read Thomas Kuhn's "Structure of Scientific Revolutions." At the time it was written, Kuhn did a trenchant job of describing how axiomatic changes influence the entire epistemological infrastructure of scientific theory.
Aboriginal Indigenous understanding of time, for example, is nonlinear (and not just in the sense of being curved as a part of the space-time continuum in relationship with gravity).
A lot of people dismiss Indigenous knowledge - there are quite a few negative stereotypes about us - but at least some of our science / ways-of-being are very thoroughly grounded in the astute observation, mindful / brilliantly aware interaction with the world (i.e. a parallel of scientific experimentation), and wisdom of countless millennia.
FFI, the current draft of Chapter 2 of my (in process) Ph.D. dissertation has a discussion of some of the axiomatic limitations of contemporary scientific world-views (linked to http://www.maquah.blogspot.com/ ).
I'm still working on it; and am interested in discussing it.
Would you say you are a "believer" in gravity too? Those just seems to be a strange choice of words to me if you consider the theory of evolution to be valid, and you think God doesn't exist. How can you be a "committed atheist", does it involve the difficult task of making sure you don't go to church on sunday, don't ever read the bible and never accidentally exclaim "oh, God/Jesus/Buddha/Allah!" if something horrific happens in front of you?
It sounds like you are being just as religious as religious people. I'm not saying that any higher power or intelligence in the Universe would necessarily conform to anything that people currently consider to be God, but it seems to me that the only way you can be "committed" is by purposely ignoring any ideas that involve any higher forms of existence. Generically sweeping away certain ideas just because you have committed yourself to a different set of beliefs seems to be a bit foolish. As someone who considered themself a Christian for the last decade but have recently been having doubts and exploring other ideas because of the growing evidence support evolutionary theory, and just some of my own internal conflicts, I'm definitely not being hypocritical by saying that
which is totally what she said
Figuring out the rules is just the first step. The set of all possibilities under those rules should be staggering to any level of intellect and experience.