What Is the Black Hole Information Paradox?

[Judi Lynn]

By Paul Sutter 5 hours ago


Paul M. Sutter is an astrophysicist at The Ohio State University, host of Ask a Spaceman and "Space Radio," and author of "Your Place in the Universe." Sutter contributed this article to Space.com's Expert Voices: Op-Ed & Insights.

The universe really likes its information. It doesn't like to create new information, and it doesn't like to destroy any of its existing information.

In fact, "like" is far too weak of a word. As far as we can tell (and we've worked really, really hard to check), information is neither created nor destroyed: information throughout the universe simply persists.

Except in black holes. Whoops. Let's explain.

Information overload

First, we need to decide what we mean by "information" and why it ought to be preserved. Physics is ruled by determinism: we can use the laws of physics to predict the future behavior of a system. That's kind of the entire point of physics. Whether it's a particle sitting in a box or a complex chemical reaction or the whole entire universe, our knowledge of physics allows us to make firm, reliable predictions that take our knowledge from the present into the future.

And that same technique allows us to dig into the past. If we know all there is to know about a system, then the same laws of physics that extend into the future also extend into the past — we can run the clock forward or backward, seeing how that system has behaved or will behave with equal ease.

More:
https://www.space.com/black-hole-information-paradox-mystery.html?utm_source=notification