## Wednesday, November 26, 2008

### David McMahon: String theory demystified

The following review was posted to amazon.com, too.

I actually love the book, its format, and its focus. Imagine that your task is to take Polchinski's textbook on String Theory and compress both volumes to 320 light pages or so.

You have to include some basics of GR, QFT, abstract classical mechanics but also the CFTs, bosonic strings, light cone gauge, T-duality, symmetries, RNS superstring, heterotic strings, D-branes, AdS/CFT, black holes. But you also add some material that was not yet fully covered in Polchinski's book such as tachyon condensation on D-branes and the speculative field of string cosmology, among others.

I think that if you realize your task well, you will end up with a book very similar to McMahon's book. As a kid or undergrad, I would actually love the playful format of the book, the icons and big headlines. In fact, I like it even now. It's the format that succeeds to attract the reader's attention and give him or her the (semi-realistic) feeling that the knowledge needed to fully master string theory is of encyclopedic character and "learnable" in a finite time.

Although the brevity of many explanations will clearly make it insufficient for all readers to understand the true origin of all results and steps, this is a book focusing on real, solid scientific arguments.

This is a simplified but technical, not popular, book that won't overwhelm you with postmodern philosophical babbling, trying to convince you that it can replace the calculations and lead you instantly to "big" conclusions without any hard work. It is a book that shows the actual correct calculations and derivations, albeit in a simplified form. Most importantly, the answers are pretty much universally correct, as far as I could check, and they uniformly cover the basic topics that are important for actual researchers in modern high-energy theoretical physics.

If you're a college student, high school student, or a mathematically skilled "semi-outsider" who is bright enough to learn advanced theoretical physics, please ignore the other reviewers who clearly have no idea what theoretical physics actually is, and buy this book. You may like it, too.

#### 1 comment:

1. Thanks for the review! I picked this up randomly at a bookstore and was enthralled. It opened my eyes that string theory really was no worse or harder than other physics, just very specialized and clever.

And as I encountered material I did not understand, I found that either or both of: good references lists for a more serious review of the material, or earlier books in the Demystified series that covered the material (several also by McMahon).

Lastly, the book also reminded me why I miss physics and that computer programming, although lucrative, is often rather boring.