How does one explian the behaviour of cosmic strings?

Question

I'm trying to explain it to my 15-year old cousin who got curious and read some book on time travel.Somehow, I just can't put it through to him. Help me!!!

Answer 1

In all honesty you can't. String theory is so mathematically complex that you basically need a PhD in string theory to understand it, in fact most PhD physicists who are not string theorists don't understand it, nor do the want to (and a lot of them are opposed to it).

String theory is a very dangerous endeavor. Some of the stuff it suggests (like time travel) are fun to think about, but it has yet yielded an experiment that could be used to test its validity. There has never been anything observed, no measurement taken, that could prove sting theory true or false. So far, it is only a set of very complicated mathematical expressions that may or may not describe the world we live in.

I think its great that your cousin has taken an interest in physics. But I think it would be best if you steer him away from books on string theory. There are many fascinating physical phenomena that have been observed that have nothing to do with strings. I would suggest that he read "1 2 3 ... infinity" by Gamow.

Answer 2

Cosmic strings are hypothetical defects in the makeup of space caused where two volumes of the universe went through very exotic quantum changes independently and then met. They are purely a mathematical contrivance. No one has seen one and no one has measured one and there is no proof that they exist. Tell him the book on time travel is just about as scientific as a superman comic book.