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Author Topic: Is Information carried away from Black Holes by Radiation?  (Read 1791 times)

Supercryptid

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Is Information carried away from Black Holes by Radiation?
« on: 02/10/2013 04:25:09 »
I was doing some thinking today when a diagram came to mind that I saw a while ago in a book entitled Black Holes & Time Warps by Kip S. Thorne:

Here are quoted passages related to the image I took from the book:

Quote from: Page 281
A blackboard was covered with equations, thick as leaves on a walk, and three sentences in English: Price's Theorem: Whatever can be radiated is radiated. Schutz's Observation: Whatever is radiated can be radiated. Things can be radiated if and only if they are radiated.

Quote from: Page 281
This quote requires some explanation. "Schutz's observation" was facetious, but Price's theorem, "Whatever can be radiated is radiated," was a serious confirmation of a 1969 speculation by Roger Penrose.

Price's theorem is illustrated by the implosion of a mountain-endowed star. Figure 7.4 depicts the implosion. The left half of this figure is a spacetime diagram of the type introduced in Figure 6.7 of Chapter 6; the right side is a sequence of snapshots of the star's and horizon's shape as time passes, with the earliest times at the bottom and the latest at the top.

As the star implodes (bottom two snapshots in Figure 7.4), its mountain grows larger, producing a growing, mountain-shaped distortion in the star's spacetime curvature. Then, as the star sinks inside its critical circumference and creates a black hole horizon around itself (middle snapshot), the distorted spacetime curvature deforms the horizon, giving it a mountain-like protrusion. The horizon's protrusion, however, cannot live long. The stellar mountain that generated it is now inside the hole, so the horizon can no longer feel the mountain's influence. The horizon is no longer being forced, by the mountain, to keep its protrusion. The horizon ejects the protrusion in the only way it can: It converts the protrusion into ripples of spacetime curvature (gravitational waves-Chapter 10) that propagate away in all directions (top two snapshots). Some of the of the ripples go down the hole, other fly out into the surrounding Universe, and as they fly away, the ripples leave the hole with a perfectly spherical shape.

Quote from: Page 283
How does this mountain-endowed implosion relate to Price's theorem? According to the laws of physics, the horizon's mountain-like protrusion can be converted into gravitational radiation (ripples of curvature). Price's theorem tells us, then, that the protrusion must be converted into gravitational waves, and that this radiation must carry the protrusion completely away. This is the mechanism that makes the hole hairless.

So my question is as follows: Has anyone ever considered that this gravitational radiation may be the mechanism by which at least some part of the information is preserved and leaked back into the Universe when a black hole is formed or consumes an object? Any asymmetrical object that collapses into a black hole should produce lumps on its event horizon that are radiated away in accordance with Price's theorem. If one could collect and analyze these waves, shouldn't it be possible (in principle) to reconstruct the shape and perhaps mass distribution of the object that became the black hole? If a tiny (likely sub-microscopic) lump is formed briefly on the horizon at the moment that a black hole consumes an object, then couldn't analysis of the resulting gravitational waves yield not only the mass and configuration of the object at time of consumption, but also the place and time it was consumed?
« Last Edit: 02/10/2013 04:27:29 by Supercryptid »

jeffreyH

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Re: Is Information carried away from Black Holes by Radiation?
« Reply #1 on: 04/10/2013 05:51:51 »
Light can't escape from a black hole but obviously gravity can otherwise it is a circular reference. The escaping gravity should relay information on the mass of the black hole. We can't detect that yet.

jeffreyH

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Re: Is Information carried away from Black Holes by Radiation?
« Reply #2 on: 07/10/2013 23:05:12 »
Correction to my last post. If the black hole is spinning there would only be the gravity from the protrusion which was outside anyway and the information was never lost in the first place.

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Re: Is Information carried away from Black Holes by Radiation?
« Reply #2 on: 07/10/2013 23:05:12 »