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The Black Hole information loss problem is unsolvable

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131–140 of 143 posts

Re: The Black Hole information loss problem is unsolvable

#131

Earlier quoted context omitted.

Rather than delving into whether additional assumptions is related to the complexity of a theory, which I think is a largely pedantic debate, I think we don't disagree as much as you perceive. > not something that needs to be explained I agree, and I'm saying that Sabine is discounting the same tool that you used to reject my hypothesis. That is my point. If there is an explanation for BHIP that does not introduce an…

I entered this discussion merely to point out what I saw as a problem with an example that you chose to make your point with. If you think that leads to a pedantic debate, then maybe it wasn't a good example to begin with. So long as you continue to insist, as you do in your last sentence above, that this is an appropriate analogy for the point you are trying to make, I will regard it as a weakness in your position.…

The pedantic debate is because you refuse to acknowledge Occam's Razor has anything to do with the simplicity of a theory, not related to the specific example I constructed.

> Hossenfelder's argument is that there are many equally plausible (and equally speculative) ways

This is just not true. Most of the resolutions of the past required new conjectures like EP=EPR, whereas recent solutions rely on newer sort of uses of a path integral, but are still built up from basic QFT+GR.

Claiming agnosticism between those two theories is discarding Occam's Razor entirely, as the latter relies on constructing way less strong of assumptions and provides a believable mechanism for information preservation.

Re: The Black Hole information loss problem is unsolvable

#132
post #124
post #69

Earlier quoted context omitted.

There are "pure quantum evolution" processes (those described by unitary evolution of ket vector), such as atom sitting forever in its ground state or being in a superposition of different Hamiltonian eigenstates. Those are time-reversible. There are other processes which are not of such kind. Some people don't want to call those quantum processes, but they sure do have a prominent place in QM textbooks. For example…

what is the golden rule?

Formula that gives rate of transition from one state to a set of many other states, as function of perturbation strength and density of final states.

https://en.wikipedia.org/wiki/Fermi%27s_golden_rule

Re: The Black Hole information loss problem is unsolvable

#133

Earlier quoted context omitted.

> until there is confirming evidence that assertion is just mental self-gratification. I'd say this is a bit overly negative. There's value in developing theories and frameworks which aren't yet provable but should be as soon as technology or other theoretical frameworks catch up.

But those, by definition, are not theories they are hypothesis.

I'm pushing back on describing them as 'mental self-gratification', as that seems like it implies a lack of value in them, potential if not immediate.

Re: The Black Hole information loss problem is unsolvable

#134
post #95
post #91

Earlier quoted context omitted.

But why do you assume two objects of same mass but different composition will add the same mass to the black hole? Different composition means different interactions during the fall and different amount of radiated energy. Infinite number of bits can be encoded in single real number. It is hard to measure more than few digits of it, but so it is hard to measure all the information.

> why do you assume two objects of same mass but different composition will add the same mass to the black hole? Because that's what the physics says. See below. > Different composition means different interactions during the fall and different amount of radiated energy. All of that can be taken into account before the object falls into the hole; the observer outside can measure it all and deduct it from the mass he…

> "for any given mass added to the hole after all those things are taken into account, there are many different possible combinations of objects falling into the hole that can add that mass."

Approximately, sure, best scales can do around 5 significant digits and null measurements can get us few more digits. But we can't verify equality of mass to arbitrary precision. For elementary particles of same kind, we can assume their masses are the same. But there is infinity of digits available. Perhaps there are no two differently composed bodies that have the same real number as mass (too many options to be different). Then maybe any mass addition to mass of the black hole can encode all the information there is about the body.

Re: The Black Hole information loss problem is unsolvable

#135

Earlier quoted context omitted.

I entered this discussion merely to point out what I saw as a problem with an example that you chose to make your point with. If you think that leads to a pedantic debate, then maybe it wasn't a good example to begin with. So long as you continue to insist, as you do in your last sentence above, that this is an appropriate analogy for the point you are trying to make, I will regard it as a weakness in your position.…

The pedantic debate is because you refuse to acknowledge Occam's Razor has anything to do with the simplicity of a theory, not related to the specific example I constructed. > Hossenfelder's argument is that there are many equally plausible (and equally speculative) ways This is just not true. Most of the resolutions of the past required new conjectures like EP=EPR, whereas recent solutions rely on newer sort of uses…

I have explained why Occam's razor is not a simplistic and subjective matter of preferring simple solutions, and your only response to that is to keep saying I'm wrong, without saying why. That is one factor in keeping this discussion going. The other thing was your insistence that your "gravity might fail" scenario is a relevant analogy; at least you did not continue pushing that view in your latest post.

>> Hossenfelder's argument is that there are many equally plausible (and equally speculative) ways

> This is just not true. Most of the resolutions of the past required new conjectures like EP=EPR, whereas recent solutions rely on newer sort of uses of a path integral, but are still built up from basic QFT+GR.

As far as I can tell, what I wrote here seems to reflect what Hossenfelder is saying in the article. Here, for the first time, you seem to be making a reasonable argument that the specific hypotheses are not, in fact, all alike, and that they may differ in a way that at least opens up the possibility of applying Occam's razor correctly - i.e. by rejecting any that make unnecessarily broad or strong assumptions.

This brings us to Hossenfelder's follow-on point: we're going to need more data in order to figure out which, if any, is correct [1]. Without more data, neither Occam's razor nor any other principle (and certainly not subjective simplicity) is sufficient to do this - the most you can do is have a preference, based possibly on which you think is least likely to run into problems with Occam's razor. That's not enough to turn a hypothesis into a theory.

This is the point that you started this thread by objecting to, and I do not think you have yet made a strong enough case to overthrow it, though you are now making better arguments than before.

[1] I'm not sure about Hossenfelder's apparent claim that this data can only come from observing black-hole decay, but that's a separate matter.

Re: The Black Hole information loss problem is unsolvable

#136

Earlier quoted context omitted.

But those, by definition, are not theories they are hypothesis.

I'm pushing back on describing them as 'mental self-gratification', as that seems like it implies a lack of value in them, potential if not immediate.

>> I'm pushing back on describing them as 'mental self-gratification'

I said "You can have a bunch of cool math, but that's not physics. It's not scientific theory by itself. You can hypothesize that it describes the real world, but until there is confirming evidence that assertion is just mental self-gratification."

The math can be cool - and often is. It's the unsubstantiated claim that it underpins reality that is whackin' ones brain.

Re: The Black Hole information loss problem is unsolvable

#137

Earlier quoted context omitted.

Isn’t the information loss problem hypothetical in the first place? I doubt anyone has seriously tried to observe information coming out of a black hole.

I'm not a physicist so if I got anything wrong, please correct me. The problem is that information conservation is a fundamental part of quantum mechanics. QM is a hugely successful theory which has proven itself to be accurate to absolutely incredible precision. The black hole information paradox implies that there is no way for information to escape the black hole, breaking conservation of information. The implicat…

> The black hole information paradox implies that there is no way for information to escape the black hole

Not quite. When Hawking radiation is included, it becomes possible in principle for information to escape the hole. That's not the main issue.

The main issue is that any information carried by an object that falls into the hole and hits the singularity inside the black hole gets destroyed. So either that information is lost, which violates QM unitarity, or the information has to get copied into the Hawking radiation that gets emitted, which violates the QM no cloning theorem.

> One suggestion have been that the information actually never enters the black hole in the first place, it's just spread out over the surface of the event horizon.

This doesn't really help, because the information can't just stop at the horizon; if an object falls in, it carries its information with it. So "spread out over the surface of the event horizon" really has to mean the information gets copied there, which, as above, violates the QM no cloning theorem. Some physicists, such as Susskind, claim that this actually isn't an issue because no single observer will ever observe both copies of the information, but this argument strikes me as contrived (and I don't think it's been proven that it must be the case).

Two possible resolutions that seem to me to at least avoid the problems I stated above are:

(1) Quantum gravity effects change the singularity inside the black hole to something else: one commonly suggested possibility is that a "baby universe" is born there, and that baby universe carries the information that fell into the hole. In other words, the information stays inside the hole and doesn't come out in the Hawking radiation, but it doesn't get destroyed either.

(2) Quantum gravity effects prevent a true event horizon and a true black hole from ever forming in the first place. That means there is never any singularity or any place where information ever gets destroyed; quantum gravity effects end up converting all of the objects that fell into the "hole" (which is now not a true black hole, but will still look like one to us on the outside, at least for a very long time) into the Hawking radiation that the hole emits as it evaporates. So no information ever gets destroyed and no information ever gets cloned.

Re: The Black Hole information loss problem is unsolvable

#138
post #134
post #95

Earlier quoted context omitted.

> why do you assume two objects of same mass but different composition will add the same mass to the black hole? Because that's what the physics says. See below. > Different composition means different interactions during the fall and different amount of radiated energy. All of that can be taken into account before the object falls into the hole; the observer outside can measure it all and deduct it from the mass he…

> "for any given mass added to the hole after all those things are taken into account, there are many different possible combinations of objects falling into the hole that can add that mass." Approximately, sure, best scales can do around 5 significant digits and null measurements can get us few more digits. But we can't verify equality of mass to arbitrary precision. For elementary particles of same kind, we can ass…

[deleted]

Re: The Black Hole information loss problem is unsolvable

#139
post #134
post #95

Earlier quoted context omitted.

> why do you assume two objects of same mass but different composition will add the same mass to the black hole? Because that's what the physics says. See below. > Different composition means different interactions during the fall and different amount of radiated energy. All of that can be taken into account before the object falls into the hole; the observer outside can measure it all and deduct it from the mass he…

> "for any given mass added to the hole after all those things are taken into account, there are many different possible combinations of objects falling into the hole that can add that mass." Approximately, sure, best scales can do around 5 significant digits and null measurements can get us few more digits. But we can't verify equality of mass to arbitrary precision. For elementary particles of same kind, we can ass…

> 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 object's mass, then it is also physically true that there are multiple possible combinations of objects whose masses can sum to that same mass (in fact there will be an infinite number of them).

Conversely, if it is not physically true that there are multiple possible combinations of objects whose masses can sum to a given mass, there cannot be an infinite number of digits available to specify an object's mass: there must be only a finite number of possible masses, and the numbers specifying the possible masses must be such that no two such numbers add up to another such number.

Re: The Black Hole information loss problem is unsolvable

#140
post #139
post #134

Earlier quoted context omitted.

> "for any given mass added to the hole after all those things are taken into account, there are many different possible combinations of objects falling into the hole that can add that mass." Approximately, sure, best scales can do around 5 significant digits and null measurements can get us few more digits. But we can't verify equality of mass to arbitrary precision. For elementary particles of same kind, we can ass…

> 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 digits.
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