Information loss via black Holes

Naty1
Messages
5,605
Reaction score
40
This question is about the relationship between information, entropy and heat.

I think it was in the 1970's the Hawking claimed "information is lost in black hole evaporation". This did not mean it was just inaccessible, but that it has literally disappeared, gone forever.

In the Black Hole War, Leonard Susskind 2008, pg 23 discusses when he first realized this must be wrong:
What's so bad about losing a bit of information in a balck hole? Then it dawned on us. Losing information is the same as generating entropy. The virtual black holes that Stephen had so blithly postulated would create heat in empty space. . We (estimated)..that if Stephen were right empty space would heat up to a thousand billion billion billion degrees in a tiny fraction of a second.


So assuming there IS information sitting in a black hole why is heated generated
when it evaporates? Is the existing heat with the black hole "released" beyond the event horizon and exposed so we can observe its effects...is that what Susskind is getting at?? And if so was all the "hidden stuff" necessarily so hot before it became a black hole..doesn't seem so.
 
Last edited:
Physics news on Phys.org
gravitational energy converted to heat energy?? hee

perhaps the things that black hole sucked in are still inside and are breaking up to form heat energy??
 
just found this old question of mine...no, there is no matter inside the event horizon..only gravitational energy...all matter is believed destroyed...compressed into sub Planck unknown form...

and by the way, I don't think entropy and heat must inevitably accopmany each other but that relationship is not at all clear to me...
 
Naty1 said:
and by the way, I don't think entropy and heat must inevitably accopmany each other but that relationship is not at all clear to me...

Entropy is the the measure of disorder in a system. So water heating up to its boiling point is an example of a system whose entropy is increasing, correct? Particles are vibrating faster and faster causing the system's entropy to increase as water to approaches its boiling point.

I can't think of anything in nature where where a system's heat increases but it's entropy does not (or vice versa).

What exactly is not clear about that relationship to you / can you provide a situation where this is not relationship is not true?

(This discussion should be moved to the General Physics Forum)?
 
Naty1 said:
So assuming there IS information sitting in a black hole why is heated generated
when it evaporates?
Where there is information there is entropy and where there is entropy there is heat.
 
I asked a question here, probably over 15 years ago on entanglement and I appreciated the thoughtful answers I received back then. The intervening years haven't made me any more knowledgeable in physics, so forgive my naïveté ! If a have a piece of paper in an area of high gravity, lets say near a black hole, and I draw a triangle on this paper and 'measure' the angles of the triangle, will they add to 180 degrees? How about if I'm looking at this paper outside of the (reasonable)...
Thread 'Relativity of simultaneity in actuality'
I’m attaching two figures from the book, Basic concepts in relativity and QT, by Resnick and Halliday. They are describing the relativity of simultaneity from a theoretical pov, which I understand. Basically, the lightning strikes at AA’ and BB’ can be deemed simultaneous either in frame S, in which case they will not be simultaneous in frame S’, and vice versa. Only in one of the frames are the two events simultaneous, but not in both, and this claim of simultaneity can be done by either of...
Back
Top