Guruswamy Rajasekaran had his college education in American College, Madurai, and the Madras Christian College, Tambaram. Then, he joined the BARC Training School of the Department of Atomic Energy (1957) and the Tata Institute of Fundamental Research (TIFR), Mumbai (1958). He received his PhD from the University of Chicago for research under the guidance of RH Dalitz and then returned to TIFR where he worked until 1976. He was Professor and later Head of the Department of Theoretical Physics, University of Madras (1976-84); and then Joint Director, (1984-96), Distinguished Professor (1991-2001) and Raja Ramanna Fellow (2001-06) at the Institute of Mathematical Sciences, Chennai. Presently he is an Adjunct Professor at the Chennai Mathematical Institute..

Academic and Research Achievements: Rajasekaran's main areas of interest have been quantum field theory and high energy physics. His early work with Dalitz led to the discovery of shadow poles that removed a serious obstacle to the application of broken symmetry concepts and also reformulated a basic tenet of S-matrix theory. He also envisaged the possibility of molecular hadrons and gave an empirical test for their identification; conjectured the confinement of massless Yang-Mills quanta much before the advent of QCD; performed the first model-independent analysis of the weak neutral current data; elucidated the remarkable consequences of QCD with integrally-charged quarks; discovered the non-validity of equivalent photon method for the production of charged particles of spin greater than half; discovered many new forms of quantum statistics including orthostatistics; and formulated a theory of generalized Fock spaces. He was the first to do a complete analysis of neutrino oscillation data including solar, atmospheric and reactor neutrinos and thus got the upper bound on the reactor angle. He constructed the popular A4 model of neutrino mass matrix, and published more than 170 papers. .

Other Contributions: Profesor Rajasekaran has been involved in the India-based Neutrino Observatory (INO) involving 20 institutions of the country, and the Physics Programme at Chennai Mathematical Institute (CMI). .

Awards and Honours: Rajasekaran won the Meghnad Saha Award of UGC, FICCI Award for Physical Sciences including Mathematics, and SN Bose Medal of INSA. He was elected Fellow of the Indian Academy of Sciences, Bangalore; and also National Academy of Sciences (India), Allahabad..