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The Black Hole information loss problem is unsolvable

backreaction.blogspot.com

141–143 of 143 posts

Re: The Black Hole information loss problem is unsolvable

#141
post #140
post #139

Earlier quoted context omitted.

> Approximately, sure This is irrelevant to the argument; our finite ability to measure masses is not what we are talking about. We are talking about what masses are physically possible, whether or not we can measure all of them with unbounded accuracy. > there is infinity of digits available You can't have it both ways. If it is physically true that there are an infinite number of digits available to specify an obje…

It is relevant because the limitation to our measurement capability means we can't know most of the digits. We can't confirm experimentally that a given mass can be composed of "multiple possible combinations of objects whose masses can sum to that same mass". The mass number for an object can exist and yet it may be impossible to duplicate it with other objects. Imagine every object having unique ID with infinity of…

> Imagine every object having unique ID with infinity of digits.

And then, as I said, there will be an infinite number of possible combinations of other masses that will add to that mass. The fact that we can't verify that experimentally is irrelevant; your model allows it and that means that, in your model, the unique ID of a given black hole's mass would not uniquely identify the original pieces of matter that formed it, and therefore would not provide the information that you originally claimed it could provide, in the post of yours that started this subthread.

Re: The Black Hole information loss problem is unsolvable

#142

I don't fully understand the claim that all quantum processes are time-reversible. Aren't there a lot of spontaneous quantum phenomena that aren't?

Correct. This is the part of QM known as Interpretations, for which people cannot agree on a single viewpoint, and hence do not agree on which axiom to add to the theory.

The measurement / collapse / decoherence / forking-of-worlds / entanglement-with-the-environment is either time-irreversible by definition, or time-irreversible FAPP.

For example, Penrose proposes that the gravitational field induces one of these time-irreversible processes:

https://en.wikipedia.org/wiki/Penrose_interpretation

Re: The Black Hole information loss problem is unsolvable

#143

I don't fully understand the claim that all quantum processes are time-reversible. Aren't there a lot of spontaneous quantum phenomena that aren't?

Quantum processes are described by Schrodinger's equation, that is a linear differential equation in time. Consequently, it's solutions for every possible boundary conditions are always reversible.

The Schrodinger Equation is obviously wrong in gravitational scenarios, because it is expressed in a background classical t that does not exist in GR, let alone a future theory of QG.
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