George Sudarshan and Quantum Dynamics

Abstract

These are my recollections of working with George Sudarshan from 2002 to 2008 when I was a PhD student in his group. During these years I learnt a lot of physics and also witness to some remarkable occurrences.When I began my PhD studies at the University of Texas at Austin in late 2001, I already knew the name George Sudarshan. He was famous for his discovery (as a grad student) of one of the fundamental forces of nature, the weak force. However, before coming to Austin I had spent the summer of 2000 at Fermilab. There I learned at least one thing; I didn't want to study particle physics. Thus I didn't bother looking Sudarshan up. I was interested in complexity and computation and wasn't really interested in the condensed matter group or the nonlinear group. Of course, at the time I didn't know that Sudarshan hadn't worked on particle physics for a long time. And I certainly didn't know of the many other things that he had done, at least two which were worthy of the Nobel Prize.Ultimately, it was clear that Sudarshan was one of the few theorists interested in the structure of quantum mechanics and the physical world. Working with him was easy in many ways. During the semester we spent either two or three days hanging out in his office for several hours and discussed all sorts of things. During summers, he was usually away, this was a good time for the students to get the writing done. All is all, in the years I spent in his group I got to work on two of these topics and was exposed to, at least to the fascinating history, of a third topic.Sudarshan's major achievements include the V-A theory (weak force), inventing the theory of quantum optics, discovering quantum maps, the quantum semi-group master equation, quantum Zeno effect, and tachyons. Yet, many physicists I meet don't know the name George Sudarshan. Some know him for his work on quantum optics, some for open dynamics, but very few know his contributions to particle physics, symmetries, and tachyons. Many will know of the Zeno effect, yet not Sudarshan. In many cases, someone Exemplary OSID style