## Abstract

E. C. G. Sudarshan is widely regarded as the most gifted theoretical physicist of Indian origin in the latter half of the 20th century. This article describes his early student years in India, and at the Tata Institute of Fundamental Research in Bombay, before he left for USA in 1955 to work with R. E. Marshak at the University of Rochester. It then recounts his career as it evolved thereafter, and his decision to settle there. His contributions in many areas of physics, in each of which he made a distinct mark, are recalled. In particular, his work on the V – A theory of the weak interactions, and on the Diagonal Representation in quantum optics, are described in some depth and detail. Sudarshan maintained strong links with the Indian physics and scientific communities all his life. From the 1970s onwards, he was at the Indian Institute of Science in Bangalore, and then at the Institute of Mathematical Sciences in Madras, till 1990. The events of this period are recounted. Some remarks on his personality, and his views on life and philosophy, conclude the article.

## Keywords

V – A theory Zeno effect diagonal representation open quantum systems## Preview

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