Could someone explain string theory to me? I've heard of it, but never read up on it.

 

I just got a book called "The Elegant Universe". Havn't started reading yet. I just want a general idea before I start reading.

Well i'd reply but i'd just be quoting the book lying open next to me... which is the elegant universe.

 

more seriously... the basic idea is that all of the properties of the current physical theories can be explained by regarding the fundamental particles as actually resembling (in mathematical ways) tiny, vibrating loops of string. That and the universe has nine or more dimensions, but mostly they're knotted up really small and so you can't perceive more than 4. This resolves the conflict between general relativity and quantum theories.

 

To me, the book makes string theory sound really vague and speculative, but the description of other theories is good.

Is there any evidence for it? Or is it just proposed because it would tie together other theories...

So far, string theory has not made a single experimentally verifiable prediction with differs from existing physical theories (afaik). In fact, at the moment they can't even solve the equations they do have.

Originally posted by blike

Is there any evidence for it? Or is it just proposed because it would tie together other theories...

 

Well, the evidence for it at the moment is that the universe doesn't work if you combine the standard model and general relativity. Until you get a working mathematical model that you can predict from, it's all just so much hot air.

 

But as popsci books go, TEU is a good one.

 

Originally posted by Morat

So far, string theory has not made a single experimentally verifiable prediction with differs from existing physical theories (afaik). In fact, at the moment they can't even solve the equations they do have.

 

Correctomundo.

 

Originally posted by Morat

That and the universe has nine or more dimensions, but mostly they're knotted up really small and so you can't perceive more than 4. This resolves the conflict between general relativity and quantum theories.

 

I thought it was 11, with 7 as a Calibi-Yau space?

Originally posted by MrL_JaKiri

I thought it was 11, with 7 as a Calibi-Yau space?

I'm almost certain they keep on upping the number when it turns out to be easier to do that than make it work with the current number.

Originally posted by Morat

I'm almost certain they keep on upping the number when it turns out to be easier to do that than make it work with the current number.

 

Ofc it depends who you talk to as it were. It's not exactly the most rigourously defined area of physics, so its quite partisan in places.

http://www.mkaku.org/

 

Michio Kaku. Read his webpage and books. He is one of the most interesting guy to listen to.

 

His goal is to help complete Einstein's dream of a "theory of everything," a single equation, perhaps no more than one inch long, which will unify all the fundamental forces in the universe.

thanks adrian.

 

 

I'm just getting started in the book. I wish I had this back when I first was trying to comprehend relativity! The author does a great job of explaining in common terms.

And either I posted in the wrong forum, or faf moved it to the right forum

Thanks for posting the site. I wish I had this when I was in college. I had two sliderules and only Einstein to deal with.

I stll can't get why the concept of 10 dimensions is necessary.

Just aman

Originally posted by Adrian

http://www.mkaku.org/

 

Michio Kaku. Read his webpage and books. He is one of the most interesting guy to listen to.

 

His goal is to help complete Einstein's dream of a "theory of everything," a single equation, perhaps no more than one inch long, which will unify all the fundamental forces in the universe.

 

His book 'hyperspace' is really good. It's the first i've read involving string theory and makes all the ideas fairly easily accessible.

 

got a copy of TEU to start as soon as i finish it