Nikhil Ranjan Sen received DSc (1921) from University of Calcutta. He worked as Rashbehary Ghose Professor of Applied Mathematics (1924-59) and Dean, Faculty of Science, University of Calcutta; also Honorary Professor, Indian Association for the Cultivation of Science, Kolkata.

Academic and Research Achievements: Under Sen’s guidance, Kolkata became an active center for fundamental research in various disciplines of applied mathematics: relativity, astrophysics, geophysics, quantum mechanics, statistical mechanics, hydromagnetics, fluid dynamics, elasticity and ballistics. He pioneered work on the internal constitution of stars and, in collaboration with his students, he constructed stellar models based on the laws of thermonuclear-energy generation. In fluid dynamics, he led a team of workers investigating problems on the boundary layer, wave resistance, isotropic turbulence and shock waves. His study of Heisenberg’s equation for the decay of isotropic turbulence deserves special mention.

Other Contributions: Father of applied mathematics in India, Sen was one of the early popularizers of science in vernacular. He stood by his friend SN Bose, who took up the task of establishing Bangiya Vijnan Parished in Kolkata. He was Life Member of the Calcutta Mathematical Society and Indian Association for the Cultivation of Science (IACS); and Member of the INSA Council (1935-41, 1949-51).

Awards and Honours: Professor Sen was elected President of the Mathematics Section, Indian Science Congress (1936) and Vice President, INSA (1959-60)