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Black Holes Not Black After All, Theorize Physicists
KentuckyFC (1144503) writes Black holes are singularities in spacetime formed by stars that have collapsed at the end of their lives. But while black holes are one of the best known ideas in cosmology, physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely dense. Indeed, they only accept this because they can't think of any reason why it shouldn't happen. But in the last few months, just such a reason has emerged as a result of intense debate about one of cosmology's greatest problems — the information paradox. This is the fundamental tenet in quantum mechanics that all the information about a system is encoded in its wave function and this always evolves in a way that conserves information. The paradox arises when this system falls into a black hole causing the information to devolve into a single state. So information must be lost.
Earlier this year, Stephen Hawking proposed a solution. His idea is that gravitational collapse can never continue beyond the so-called event horizon of a black hole beyond which information is lost. Gravitational collapse would approach the boundary but never go beyond it. That solves the information paradox but raises another question instead: if not a black hole, then what? Now one physicist has worked out the answer. His conclusion is that the collapsed star should end up about twice the radius of a conventional black hole but would not be dense enough to trap light forever and therefore would not be black. Indeed, to all intents and purposes, it would look like a large neutron star.
Earlier this year, Stephen Hawking proposed a solution. His idea is that gravitational collapse can never continue beyond the so-called event horizon of a black hole beyond which information is lost. Gravitational collapse would approach the boundary but never go beyond it. That solves the information paradox but raises another question instead: if not a black hole, then what? Now one physicist has worked out the answer. His conclusion is that the collapsed star should end up about twice the radius of a conventional black hole but would not be dense enough to trap light forever and therefore would not be black. Indeed, to all intents and purposes, it would look like a large neutron star.
Frozen Star by George Greenstein had as a central theme that due to gravitational time dilation that we could never see a star collapse beyond its own event horizon: it would asymptotically approach it as arbitrarily close as we liked given unlimited time but never cross it. So as a natural consequence there was always a tiny but measurable probability that trapped light and thus information could escape.
Although this is a layperson's work, it is based on his published papers which provide a mathematical background.
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physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely density.
They've clearly never been to DC. I'm convinced that regions of the universe are infinitely dense.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
Chicken. It looks like chicken.
How can I believe you when you tell me what I don't want to hear?
Like a small neutron star. Only bigger.
Speed of light limitation? Probably, but how are neutrinos that have mass going 99.9999% the speed of light?
Electrons and positrons in LEP, the predecessor to LHC were going about 99.99999996% of the speed of light. That was far from infinite energy, and not even a lot by cosmic ray standards. For a neutrino to go 99.9999 would need about ~70 eV of energy, which is an order of magnitude larger than energetic chemical reactions, but quite tame by nuclear reactions. Nuclear reactions can easily produce neutrinos with energies from 0.1-10 MeV, up to 100,000 times as much.
Yeah, well... your MOM is infinitely dense.
Yours is not infinitely dense. After all, everyone penetrates her.
"Flyin' in just a sweet place,
Never been known to fail..."