Wednesday, March 30, 2011

Black Holes, Information and Parallel Universes

No, this isn't a review of A Brief History of Time by Stephen Hawking. Although, everyone should read that book. It's important to understand current scientific theory, especially one as ground breaking as the Big-Bang.

Hawking's biggest contribution to physics hasn't been the Big Bang, though. Instead, it seems to involve black holes, information and a big paradox.

I love physics, but I'm not mathematically minded. I enjoy specials on the Science Channel and that's what jump started this post. The special, The Hawking Paradox, was about the "information paradox" and was produced by the BBC. Hawking's theories about black holes all come to the same conclusion: information is lost (destroyed) in a black hole. When this happens, nothing in the universe is certain. If we are missing information in our universe, it is impossible to make predictions. We all know that we can't make a good prediction on anything, even horse racing, without a little bit of information. Having all the information allows physics to work. If information is destroyed, then cause and effect is ruled out and our own memories are suspect.

This seems a little dramatic, because, after all, black holes are very far away... right? According to the show, there are even mini-black holes everywhere. They can even be inside your brain. Scary!

As the show plays out, we find out that Hawking has a rival in Leonard Susskind, another physicist. Susskind believes that information is not lost inside a black hole: it just seems like it's lost. Instead, the information gets spread across the outside of the black hole and we can read this information and see what's going on "inside" the hole.

Hawking disagrees. Hawking's solution is that yes, information is lost in black holes. But there are parallel universes to our own that don't have black holes and therefore they cancel out the lost information.

Somehow, that's really unsatisfying! Does that mean that our universe is somehow defective? There are universes that don't lose information, but ours does. Why would that happen? Are we inside a rotting, dying universe? Can we visit the parallel universes? How do we know they are really there and if they exist, are they much better than our swiss-cheese, lossy universe?

I want the answers to these questions and am looking forward to the next BBC physics special! Hope they answer a few!