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Stephen Hawking: 'There Are No Black Holes'
ananyo writes "Stephen Hawking has proposed a new solution to the black-hole firewall paradox, which has been vexing physicists for almost two years. The paradox troubles physicists because if the firewall scenario is correct, Einstein's general theory of relativity is flouted. But the classical theory black hole cannot be reconciled to the quantum mechanical prediction that energy and information can escape from a black hole. Now Hawking has proposed a tantalizingly simple solution to the paradox which allows both quantum mechanics and general relativity to remain intact — black holes simply do not have an event horizon to catch fire. The key to his claim is that quantum effects around the black hole cause spacetime to fluctuate too wildly for a sharp boundary surface to exist. As Hawking writes in his paper, 'The absence of event horizons mean that there are no black holes — in the sense of regimes from which light can't escape to infinity.'"
Hawking: ...this means, in a sense, that there are no black holes. Only what I call "Hawking surfaces".
Layman: Does this mean it's possible to travel faster than the speed of light?
Hawking: Sure, why not.
Do not try to reconcile the event horizon. That's impossible. Instead only try to realize the truth. There is no black hole.
Does that mean that he gets his $100 back he lost to John Preskill?
That's it, science has failed once again. I'm going back to christianity.
lol
Oh, sure, easy for you to blather about Mr. Smarter-Than-Einstein AC.
Put up your research, with a name, or shut up.
Scruting the inscrutable for over 50 years.
The event horizon oscillates faster than the speed of light over a greater distance than quantum tunneling can occur. Inbound light would follow the wavefront in, only to become trapped as the next wave built outside its escape range.
Help stamp out iliturcy.
My sense, in reading a considerable number of articles about astrophysics, etc, is that we are in a period which is awaiting the next big breakthrough in knowledge, along the lines of what Newton and Einstein produced. There are still too many unknowns and ambiguities that need to be resolved by discovering a piece of the puzzle which we don't even know exists yet, and I think people are still trying to get their heads wrapped about quantum physics. That said, I'm not a physicist, just an interested lay person, so I may be wrong in that summation, but it seems many of the discussions occurring these days at least pay a backhanded nod to that sort of notion.
In this picture, there would still be astrophysical black holes in every meaningful sense of the word, i.e. condensed objects from which light would not escape. Such objects would have an "apparent horizon", which can be defined locally by the property that all lightlike geodesics are ingoing.
What these black-hole-like objects would not have is an Event Horizon, which is a global property of the spacetime, and is only defined by the behavior at asymptotic infinity. It's a neat resolution of the whole mess: way more sensible than firewalls.
But it's still just hand-waving -- note that the entire argument relies on AdS/CFT, which assumes the black holes are embedded in de Sitter space, which has a negative cosmological constant and is most definitely not the kind of spacetime we live in. And AdS/CFT is itself an unproven conjecture, although it is supported by many specific example cases. Until somebody comes up with a theory of quantum gravity, this stuff is all guesswork. Caveat emptor.
The actual paper can be found here: http://arxiv.org/abs/1401.5761. People have suggested informally ideas somewhat similar to this one before, but Hawking proposal seems to actually have the math behind it. Possibly most importantly, he can show that his predictions are a consequence of gauge/gravity duality http://en.wikipedia.org/wiki/AdS/CFT_correspondence. This suggests that this may be a testale consequence of certain string theories if one could observe a black hole under the right conditions and see that it only was pretending to be a black hole.
It means all these business idiots will stop saying "event horizon".
Proverbs 21:19
Data from the satellite orbiting Uranus confirms that the hole is, in fact, brown-ish
Newtonian Gravity isn't correct either, we still use it in limited scope. It doesn't mean that Relativity is prevented from the same usage.
But it is still far from correct and the day people finally accept that and move on, maybe some actual research will get done. Dark Matter and Dark Energy are literal blackholes of knowledge that rips Relativity apart in every sense of the metaphor.
There is hardly a contradiction, just you putting meaning where there is none.
You know that building you live in? Built with Newtonian mechanics. That's why it stays up.
And the sat-nav in your phone? That uses general relativity. If it didn't, it wouldn't be able to locate you in the right country, let alone on the right street.
Newtonian mechanics and general relativity have been proven correct many times over. What they are though is incomplete. And there's a mountain of research happening right now to work out why.
No colour or religion ever stopped the bullet from a gun
- Black Hole
Relativity is the most proven theory in the history of science. Nearly every physics major that's graduated in the past 80 years has proven out a different part of it in some new and unique way as part of their doctoral thesis. Every observation that's ever been made that seems to contradict it has later been found to be faulty or explained by some other phenomena that we hadn't understood as of yet.
Infinities exist everywhere in nature. They are naturally hard for us to understand because of our species engrained believe in the Birth/Death cycle and we feel it should apply to everything just well as it does to us.
Lastly, you are correct, Relativity will fail eventually. Even Einstein knew this. It explains "how" things work but only in limited condition and scales. Just like how Newtonian physics worked at the Macro level and at speeds and timescales humans could measure at the time it was devised, relativity only works at certain scales. But it does not invalidate the predictions of Newtonian physics, it just expands them. Eventually we will learn more and there will be a new theory that either explains it all, or at least improves on what Newtonian and Relativistic physics has shown us.
I don't think it is, no. But I do think he overstates his case somewhat. For me, the left eyebrow is raised by the need for huge quantities of "dark matter" in order to account for large scale structure of galaxies even though studies of our local region of space show no such matter exists (or is required to explain it). Now OK, if they discover some WIMPs in future I will hold my hands up, but right now being sceptical is the correct position to take on this. And if WIMPs don't exist, well, the predictions of GR won't match observation so at the very least it will need modification.
This is all notwithstanding the fact that physics simply describes the regularities of experience and apparently gives different answers to the same question depending on how that question is posed. It's still amusing to me that mathematics cannot even deal with the 3-body problem in Newtonian Mechanics adequately without resorting to perturbation methods. Then there's the regularisation issue in Quantum Theory, where infinities magically cancel each other out.
I am not a physicist, but I reiterate the need for scepticism everywhere and at all times. It's possible to be sceptical and also have "wow" moments when physicists come up with genuinely new ideas. I do sometimes wonder just how primitive our current bleeding edge ideas will look to our distant descendents.
Interesting troll. A bit heavy handed, though. If I were to grade it, if it was written by a high school student it would get a C+, if written by a college student, it would rate a D- (barely passing).
Point of interest: the Copenhagen convention suggests that there is no possibility of a physics Out There. That all physicists can do is make mental models of whatever reality might be, and play around with those models, since reality itself is unobservable without the distortions of observer bias. There are some things we think we know, and there are some things that we know that we can never know (such as what is happening in close proximity to a singularity, or why is Pi 3.14159... and not something else). And it turns out that because there are some things that we know we can never know, we can't be sure about any of the things we think we know.
So, yes, AC is completely correct: relativity is wrong. Also quantum mechanics is wrong. Also classical physics is wrong. It is all wrong. So what? Asking whether this stuff is right or wrong is asking the wrong question. The right questions to ask of any physics model are: How useful is it, and what is its scope of usefulness?
We are the tool using monkeys. We are not Gods. Don't sweat the Really Big Stuff. Do something with the tools: make more tools, make some fun toys and games. That's what we do best. And, that's all that we can do.
Will
If you add the mass of the egos of those on slashdot, that solves the whole galaxy missing mass problem.