TITLE: Where to start with research regarding maslov index/class
QUESTION [5 upvotes]: Hi,
I am a physicist and currently doing my bachelor thesis about geometric quantization.
In the book by Bates and Weinstein I encountered the Maslov index, which seems to be very important :-).
But unfortunately my education didn't include anything in the direction of algebra beyond the scope of basic linear algebra. My present research about this topic showed that the Maslov class is an element of the integral cohomology of the manifold. But I couldn't find an introduction or something like this to 'integral cohomology' and I was lost in the big realm of cohomology.
(For example: What is the difference of de Rham cohomology, Cech cohomology, Cech - de Rham cohomology and the needed integral cohomogogy).   
So could someone provide me with a "path" along the topics I have to study to be able to understand Maslov classes. 
Thanks in advance,
Tobias!

REPLY [3 votes]: There are different incarnation of the Maslov index.  The one that I prefer is the one proposed in Arnold's paper suggested by Igor Rivin. The paper  by Cappell-Lee-Miller suggested by  Greg Friedman is also an excellent source. (These two papers  helped me understand this concept but they addressed primarilty to a mathematical audience.) 
Maslov  introduced his index  in his investigation of  asymptotics of certain oscillatory  appearing in quantization problems. I suspect this  is closest to what had in mind.  It is  sometime known as the  Hormander index.    Section 3.4 of Duistermaat's book Fourier Integral Operators  has a rather   efficient  description of the Maslov index.  As an aside, the operators introduced and investigated by  Maslov are special examples of Fourier integral operators.