Ennackal Chandy George Sudarshan (also known as E. C. G. Sudarshan; 16 September 1931 – 13 May 2018) was an Indian American theoretical physicist and a professor at the University of Texas. Sudarshan has been credited with numerous contributions to the field of theoretical physics, including Glauber–Sudarshan P representation, V-A theory, tachyons, quantum Zeno effect, open quantum system and Lindblad equation, spin–statistics theorem, non-invariance groups, positive maps of density matrices, and quantum computation. Early life Ennackal Chandy George Sudarshan was born in Pallom, Kottayam, Travancore, British India. He was raised in a Syrian Christian family, but later left the religion and converted to Hinduism following his marriage. He married Lalita Rau on December 20, 1954, and they have three sons, Alexander, Arvind (deceased) and Ashok. George and Lalita were divorced in 1990 and he married Bhamathi Gopalakrishnan in Austin, Texas. He studied at CMS College Kottayam, and graduated with honors from the Madras Christian College in 1951. He obtained his master's degree at the University of Madras in 1952. He moved to Tata Institute of Fundamental Research (TIFR) and worked there for a brief period with Homi Bhabha as well as others. Subsequently, he moved to University of Rochester in New York to work under Robert Marshak as a graduate student. In 1958, he received his Ph.D. degree from the University of Rochester. At this point he moved to Harvard University to join Julian Schwinger as a postdoctoral fellow. Career Sudarshan made significant contributions to several areas of physics. He was the originator (with Robert Marshak) of the V-A theory of the weak force (later propagated by Richard Feynman and Murray Gell-Mann), which eventually paved the way for the electroweak theory. Feynman acknowledged Sudarshan's contribution in 1963 stating that the V-A theory was discovered by Sudarshan and Marshak and publicized by Gell-Mann and himself. He also developed a quantum representation of coherent light later known as Glauber–Sudarshan representation (for which controversially Glauber was awarded the 2005 Nobel prize in Physics ignoring Sudarshan's contributions). Sudarshan's most significant work may have been his contribution to the field of quantum optics. His theorem proves the equivalence of classical wave optics to quantum optics. The theorem makes use of the Sudarshan representation. This representation also predicts optical effects that are purely quantum, and cannot be explained classically. Sudarshan was also the first to propose the existence of tachyons, particles that travel faster than light.