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rahuldandekar
2007-Jan-14, 10:59 AM
Our Physics department at college recently arranged a lecture on General Relativity. The proffesor explained parts of everything, from differential geometry to g mu nu. But there were some pages on Tensors which were pretty much greek and latin (literally, with all those greek letters).

So, what I'm asking is, to read a book on GR, how much background in mathematics and physics do you need? Tensor calculus and Classical Mechanics (Lagrangians) is ok?

Tensor
2007-Jan-14, 03:21 PM
Our Physics department at college recently arranged a lecture on General Relativity. The proffesor explained parts of everything, from differential geometry to g mu nu. But there were some pages on Tensors which were pretty much greek and latin (literally, with all those greek letters).

So, what I'm asking is, to read a book on GR, how much background in mathematics and physics do you need? Tensor calculus and Classical Mechanics (Lagrangians) is ok?

I think I qualified to answer that. I got to the point where I knew all the standard non-mathematical explanations of GR, but I wanted more.

I started with college classes in Physics and Calc series. Then took Diffy Qs and Linear Algebra classes. At this point, I was out of options at the local community college. So I went out and got books on Differential Geometry (which includes tensor calculus)(DG), and the bought college level textbooks on SR and GR. This was helped along by some pretty nice professors at different colleges that I emailed (explaining what I was doing) when I had questions I couldn't figure it out. If you have a basic understanding of DG, most of entry level textbooks on GR will take you through the math.

I will admit to having a lot of holes in my knowledge, but I can usually follow along and work things out on my own (it probably takes me a lot longer than for someone who actually works on it). The problem with this, is that I sometimes have trouble trying to explain what the math is actually saying. This indicates that I may not understand it enough to really explain things very well, but I just wanted to understand enough.

That was my path. It really depends on what you want. Just to understand the basics, the above will probably work. To actually work out physical problems (instead of just being able to follow along), you would probably be better off actually taking classes on it. You may have an advantage over me as you may have some people or professors where you are at that can help (I didn't have anyone locally to help me with this).

rahuldandekar
2007-Jan-15, 02:17 AM
Thanks for the reply. :)

Yep, I too have a lot of non-mathematical GR knowledge, and want to learn more.

But what's bugging me is that I have to do lots of mathematical physics first. The problem is, I think, that the physics undergrad course at Mumbai Uni does not have lots of mathematics (yep, only linear algebra and diff qs). We have SR in the Third (final) year, and GR at MSc level is optional.

I have a mathematics ebook that includes intro Tensor Calc (here (http://www.physics.miami.edu/~nearing/mathmethods/)) and my college library might have books on DG and GR.

The only problem is time. I am already swamped solving problems from the Mathematical Physics book. :doh: My problem is, I am always too eager, and I ignore problem-solving. :whistle: