An Impossible Information Paradox In Black Holes Seems to Break Physics!

This is a picture of a black hole from the Event Horizon Telescope from NASA, captured from a galaxy called M87, 55 million light years away from Earth.

A black hole occurs when a star exhausts most of its nuclear fuel and collapses under its own gravitational pull.

If it's a large enough star, its compactification results in a gravitational pull so strong that nothing can escape, not even light.

That's why it's black.

In 1976, legendary physicist Stephen Hawking proposed that black holes, mysterious enough as they are, do something that should be impossible according to the laws of quantum mechanics.

They destroy information.

This is a paradox because it should not happen.

Information should be conserved in the universe, because if it's not, then it could mean that causality could be violated.

In other words, random inexplicable events could happen that are not linked to prior events.

This has huge implications for the way we think our universe works.

The order of events, time, and the deterministic laws we think we know could all be garbage.

Surely that's impossible.

What is the black hole information paradox? How are causality and information conservation correlated? And how do black holes potentially violate it? That's coming up right now.

The first question you might have is, what does information have to do with black holes? I'll explain that first.

The way physicists think of information may not be the way you think of it.

They usually don't mean information like on a hard drive or a book.

These are things that can be encoded with zeros and ones.

They describe information as the number of yes-no questions that must be answered to fully specify the properties of a system.

By the way, this definition of information is also the way entropy is defined in physics.

Entropy and information are closely linked.

The more information that is necessary to specify a system, the higher the entropy of the system.

One of the basic laws of physics is that information is never lost.

Information always stays in the universe.

In terms of entropy, the second law of thermodynamics states that the entropy can never decrease.

So this also has implications for information because if information could be erased, then that would mean that entropy could be decreased.