Why an Impossible Black Hole Paradox Seems to Break the Laws of Physics!

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NOTES & REFERENCES

CHAPTERS
0:00 The importance of information conservation
1:29 What does information have to do with Black Holes?
3:54 MyHeritage
6:40 How is information conservation related to determinism?
9:05 How did Stephen Hawking show that Black Holes violate information conservation
12:30 Black hole information paradox
12:50 Where does the information go? Leading theories

SUMMARY
In 1976, Stephen Hawing proposed that Black Holes, do something impossible according to the laws of quantum mechanics. They destroy information. This is a paradox because information should be conserved in the universe. If it is not, then it would mean that causality could be violated. Random inexplicable events could happen not linked to prior events. This has implications for the way we think our universe works. The order of events, time, and the deterministic laws depend on information conservation.

What does information have to do with black holes? The way physicists think of information is not like on a hard drive or a book. They describe it as the number of yes/no questions that must be answered to fully specify the properties of a system. This is also the way entropy is defined in physics. Entropy and information are linked. The more information that is necessary to specify a system, the higher the entropy of that system.

One of the basic laws of physics is that information is never lost. It always stays in the universe. In terms of entropy, the second law thermodynamics states that entropy can never decrease. So if information could be erased, that would mean that entropy could be decreased, which is not possible.

If you burn a book, the book’s information doesn’t really get destroyed because the information is still retained in the universe. All the elementary particles of the book are preserved in the soot and smoke resulting from the burning. In principle, if we had the technical capability to look at the quantum state of all those elementary particles, even after the burning process, we could recreate their quantum state immediately prior to that, and then immediately prior to that, and so on until we recreated the book.

How is this information conserved? This is closely related to determinism in physics. The fundamental laws of physics are deterministic, i.e. given the full information about an initial state of a system, you can in principle predict the evolution of that system. That is, you can predict its state in any later moment in time. And you can also reconstruct the earlier states of the system.

There is a cause and effect for all interactions. What follows is that you can’t have two different initial states evolve into exactly the same final state, because then you would not be able, even in principle, to reconstruct the previous state of the system. So, “information loss” for a physicist means: having many different initial states evolve into exactly the same final state. If that were the case, the idea of determinism would be lost. Conservation of information, therefore, is what makes the universe deterministic. And we can infer from this, a predictability and causality in the universe.

If a book falls into a black hole, it's not accessible to anyone outside the black hole and is lost forever. But prior to Stephen Hawking, this was not considered a big deal, because it was thought the information in the book was at least contained inside the black hole, and therefore still in the universe. We can’t get to it, but it was there.

But this idea was shattered when Hawking showed that Black holes evaporate slowly over time, and that given enough time, the entire black hole would evaporate into photons or black body radiation. But this radiation does not contain enough information to recreate the book. So where does the information go?
#blackholes
#stephenhawking
There are several theories. One is that the information that goes into making a black hole is somehow encoded in the evaporated Hawking radiation. A recent paper suggests that when the effects of quantum gravity are taken into account, Hawking radiation could contain information. Others suggest that there is a correlation between every radiated particle of a black hole and the information that fell into it similar to entanglement. Another theory is that Black holes are gateways to other universes and that the seemingly lost information is actually stored in another universe. Bottom line is that this paradox is not resolved.

[chuckz]

Dude really does explain complex questions simply.

[IncompleteTheory]

As long as you keep emitting information, I'm good!

[jimsykes]

This is why, when I skipped school in middle school and they called my dad, he retained the information that I was at home playing video games and busted me in the act.

[bipolarbear]

If we assume our universe is part of a larger multiverse, and that black holes may be portals to other universes within the multiverse via an Einstein-Rosen bridge (wormhole), then the information is not lost in a black hole, it’s still exists within the greater multiverse, and so there is no information paradox. Think ‘outside the box’.

[th_St_Air]

@3:32 they’re super intelligent beings that can track quantum states of matter, but they still haven’t invented yoga pants or hoodies? 🤔

[googoogjoobgoogoogjoob]

I guess we've added it to the long list of things we don't know.

[Starchface]

If the information inside the event horizon leaves our universe and arrives in another, _it has still left our universe._ That is not a solution to the Paradox.

[dougaltolan]

"infinite capability"
Yeah, that's where your paradox becomes an irrelevant pipe dream.
Much of day to day physics breaks at the extremes, black holes are just one such extreme.

[thomassturm]

First: physicists do not study philosophy nowadays. Otherwise they would know that "determinism" in a strict sense is logically impossible. Yes, you can have different outcomes from exactly (in any way, shape or form) the same starting conditions. Or: find some "hidden parameters" that let you predict exactly when a single atom of an unstable isotope will decay. There are no such parameters. The decay will have an effect, however.
This means that you can have identical starting conditions down to individual gluons or whatever you fancy as the absolute bottom line of reality and let the conditions evolve: if your timescale is large enough (as compared to the interactions between those fields or "particles"), say, a second, you'll have vastly different systems at the end of it. If "god" created another Universe, exactly to the minuscule detail of our own, and pressed "GO", it would not even likley lead to you, yes YOU, thinking: what sort of rubbish am I reading here, some 13+ billion years later.

Determinism is a good guide if all things you consider are "big". But to conclude it is absolute is just folly. So: if you burn a book you have written and you burn it before anyone has ever read it, it is gone. For good. Not even "gods" - whatever you imagine they can do - could read it afterwards. When you die, all information contained in the book will be gone. Comforting thought, isn't it?

Second: Physics really does not want to accept black holes. Actual physicists love them because you can write all sorts of rubbish about them and get published. Like the paper I read about one year ago, which claimed that basically as a "last breath" a black hole would convey all "information" in the very moment it dissolves completely. It actually got published in a physics journal (should be easy to find, though I can't be bothered right now) and it wasn't any more scientific than little red riding hood. If you throw your unique book at a large enough black hole, it would still be perfectly readable past the event horizon. Just not for anything present or even imaginable in our universe, ever. Mind you, burning it and scattering the ashes in the wind has exactly the same effect. Regarding black holes, however, Physics demand a "singularity" somewhere, with gravitational forces going towards "infinity". Sorry folks, there is no such thing. I wish as a philosopher I could help you out, but all I can say is πάντα ῥεῖ (panta rhei: Simplikios, around 500 bc): the curvature of spacetime is never infinite (and nothing ever is "eternal", btw.), it is perfectly smooth and not quantized. There is no such thing as will not allow "flow" and never will be. At least, give these premises a try: so far, all I can see are attempts to wriggle around them somehow. Black holes exist. Infinity only exists in Mathematics in various forms, but not in real life. As long as physics treats black holes as some kind of "otherworldly" entities rather than things that definitely exist in our universe, we will be stuck at wild guesswork.

[markofdistinction]

I heard that two physicians got married. They formed a new pair of docs.

[mineduck]

Sure, if you loosen the usage of the word 'information' to an astounding degree.

[XochitlPreslarar]

Your videos are always so entertaining and informative! Thank you for that! 🐱💞

[stephenzhao]

6:42 The fundamental laws of physics are deterministic, that is, given the full information about an initial state of a system, you can (in principle at least predict the evolution of that system. That is, you can predict its state in any later moment in time. And you can also reconstruct the earlier states of the system. You might object to this by pointing out that quantum mechanics is considered a non deterministic theory. That's true, but it's only with respect to measurement. In other words the result of a measurement is not deteministic, but the underlying laws of quantum mechanics are different. The evolution of the wave function that determines the quantum state of any system is completely deterministic in producing a bprobabiligy of an outcome. The probability of all outcomes added together is always equal to one. This is called the Principle of Unitarity. ) 7:34

[jonathanlenz]

Two states CAN evolve into the same final state, no? Determinism is only lost for reconstructing the past, not for a deterministic future. For example, many universes may lead to the same heat death. Or many books may lead to the same hawking radiation. Or many wave functions may lead to a particle in the same location, even if the wave is reconstructible, and so no information is lost about the wave a particle rides.

[viralsheddingzombie]

A paradox will always appear to break the laws of physics. That's what a paradox is by definition. And that is why I always say there is no solution to a paradox. It is simply a lack of information. It doesn't matter where the information went or how the information appeared or disappeared. Sean Carroll calls it the "universal wave function." We can never hope to define such a function that describes the entire universe.

[manny]

Why should the universe care about our human created mathematics? After all, the math is only an attempt to model the real universe.

[carparkmartian]

Pretty good explanation.
Here's the thing, the particles that fall into the black hole have two types of information - intrsic information and extrinsic information. The intrinsic information is related to its intrinsic properties which are - for the electron ( for example), its electic field, spin and magnetic field ( magnetic dipole moment). The extrinsic information relates to its potential energy - which is its mass - and mass - energy and its massy derivatives such as momentum, kinetic energy and angular momentum.
In accounting information of particles we only account for the extrinsic information and tgat is handled most typically in the total energy equation - which must always balance across an event.
When it comes to intrinsic and quantum theory - we actually directly erase that information with the charge and spin conservation laws. We do this by assigning negative particle information and positive particle information then add that information ( charge or spin) which directly erases that information. This is of course foundationally wrong and inconsistent with conservation of information, unitarity and linearity.
Now apply that to the electron- positron annihilation event and you will see where all the antimatter of the universe went. ( hint they didn't get erased or annihilated- they simply bound neutralised the electric fields and "disappeared".
We can still directly detect them by detecting the electric permitivity of empty space. I'll let you worth that out.
So when a particle falls into a black hole both its extrinsic and intrinsic information falls in. That's a lot more information than was accounted for by hawking or anyone else for starters. The subunits of that information is preserved inside the horizon of the black hole as well as the fields that emanate from the black hole.

[imatthewryan]

send your DNA to a private company? nah that wild

[jamesraymond]

Here is a question for a theoretical physics professor: A student proposes to work on the conservation of information problem. Should the professor approve it, or advise against it, saying that it will be a waste of his career? I suspect he will advise the student to work on another, more feasible topic.

[pauldhoff]

After taking a Google Plex years to come back out all messed up I don't care.