Textbook for a class I took from George Sudarshan, which I will never forget. George discovered the electro-weak force (V-A theory) and founded quantum optics with Glauber. He was nominated numerous times for the Nobel prize in physics but has never won it. George is one of the most deserving individuals that has been "snubbed " by the Nobel committee. The book itself is very readable for anyone who can read Scientific American.