Why Stephen Hawking takes a big U-turn at this point?
If there’s one thing in astrophysics that has managed to continuously attract people’s interest (besides time travel), it is black holes, the areas of space and time, so dense, that nothing, not even a beam of light can escape their pull. But now, the pioneer Stephen Hawking has brought out a paper stating that the Black Holes, in all probability, might be non-existent. In his Black Hole Bio “There are no black holes,” Hawking writes about his theory. He quickly qualifies his dramatic statement, by stating, it’s only true “in the sense of regimes from which light can’t escape to infinity.”
The objects, already confirmed by astrophysicists, still exist, but just not the way we thought they did. If Hawking’s paper (based on a talk he gave last August) is correct, maybe what’s going on is this: classically, black holes have an event horizon surrounding them, which serves as the effective boundary of the black hole. Once you are past the event horizon, you can never get out again, no matter what, even if you were a beam of light or a neutrino or a something. The problem arises when quantum physics, the crazy science of the very small, enters the mix. A recent astrophysical paper suggested that when quantum physics is taken into account, the event horizon would actually be, as Hawking puts it, “surrounded by firewalls-bolts of outgoing radiation that would destroy any in-falling object.” This is at odds with the prevailing Einsteinian theory. Nature elaborates: Someone/thing in free fall should perceive the laws of physics as being identical everywhere in the Universe — whether they are falling into a black hole or floating in the empty intergalactic space. As far as Einstein is concerned, the event horizon should be an unremarkable place. Hawking’s head-scratcher to resolve the firewall issue, suggests, surprise! —there is no event horizon, but, instead there is an “apparent horizon,” which doesn’t hold stuff back to be trapped forever, so much as just to delay and scramble it. That’s what he means when he says, “There are no black holes.”
The classical idea of a black hole as an object that never lets things go might be flawed. Hawking’s analysis was published on arXiv, a preprint server, and thus hasn’t been peer-reviewed. The Nature story quotes a bunch of other physicists saying the idea is plausible, but it’s still a good idea to be sceptical about it. There might be another solution to the firewall paradox that leaves black holes intact — or, Hawking could be wrong, and the right solution could be something even crazier. It’s hard to say because Hawking left the actual nuts and bolts of his idea to other researchers. “The correct treatment remains a mystery,” as he told Nature. (His 3-page paper contains not a single equation —though, don’t worry, it’s still fairly incomprehensible if you’re not severely into this stuff.)
So, once again Hawking’s work could transform everything we know about black holes. Maybe the universe’s most greedy objects do eventually let go of their treasures, under certain conditions. Whatever the case, odds are they won’t loosen their grip on the public imagination.
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- Why Stephen Hawking takes a big U-turn at this point? - February 7, 2014