11-19-03 - 2


I finally watched the Nova on String Theory, since I'm home sick for the day. Horrendous, and not just for someone who knows some physics, but just horrendous in general. Four hours and almost totally devoid of information, very repetetive and insultingly simplified. I think that any smart person who doesn't know physics would have felt the same way. When I watch the Novas on other fields, biology, chemistry, etc. I find them to be too simple, lacking in depth. There's also a way that programs like that could talk to multiple levels at the same time; just toss out a little bit of more advanced stuff once in a while and you'll keep the higher level people occupied. In fact, the program was very un-compelling. String Theory is really magical and amazing stuff; when I learned it, it sent shivers down my spine, literally, the things that come together to make it possible are just astounding - the magical cancellations of the infinities, the dimensions and symmetry groups, the fact that it just so happens that the Standard Model is found inside the only possible string theory, it is like the theory was meant to be - and that's why people have stuck with it through so many difficulties. The show gave none of that impression, really.

There is no good description of quantum mechanics for the lay person. I bet I could write one. Quantum mechanics is definitely correct; even if it's not the way the universe works, it's correct as a model. That is, even if the universe works in some other unknown way, QM is still correct as a predictive model. In fact, under some philosophies of science, all you can ever do is form a predictive model. That is, let's say we did have a "Theory of Everything" - let's say String Theory worked out and explained everything. Now, is the universe actually made of strings? Who knows! In fact, what does it mean to say "actually made of" ? All we can say is that string theory is an incredibly good *model* of the universe. We can say that the model of the universe acting as strings predicts the same thing that actually occurs. I think that even many scientists fail to grasp this and believe that when they work with strings, it means the universe is actually made of strings. That's ok, it's a form of religion, and it helps to make thought clearer.

Quantum mechanics requires you to visualize branching amplitude trees, state overlaps and collapses, probability amplitude spreading and coupling and forming conditional probabilities, etc. Even plain probability is very difficult and paradoxical to most people, amplitudes (square roots of probabilities) are even more bizarre, and the idea that the universe works this way is just incomprehensible to most.

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