Ramanathan got his B.Sc in Mathematics at Ramakrishna Mission Vivekananda College, and was recruited to attend TIFR, where he got his Ph.D. in Mathematics in 1976. His thesis on moduli for principal bundles was published in 1996 in two papers in Proc. Indian Acad. Sci. three years after his death.^[1]

Ramanathan, was a Professor of Mathematics at the TIFR in Bombay, India. He has also been employed at University of Bonn, Johns Hopkins University and University of Illinois at Urbana-Champaign. Ramanathan made significant contributions to many areas of mathematics, including moduli of vector bundles, Gauge theory, algebraic geometry in positive characteristic and representation theory.

The Council of Scientific and Industrial Research awarded he and his collaborator Vikram Bhagvandas Mehta the Shanti Swarup Bhatnagar Prize for Science and Technology (the Indian Presidential award for achievement in the mathematical sciences) in 1991 for his work in algebraic geometry.

Ramanathan was third of four children born to a Tamil family S. RM. CT. Annamalai and Lakshmi. Ramanathan was crippled by adult onset polio in his late teens, and he used a crutch for the rest of his life.^{[citation needed]}

During his tenure as a visiting professor at University of Illinois at Urbana-Champaign, Ramanathan died in Chicago, Friday, 12 March 1993, of complications following treatment for a heart attack. He is survived by his wife RM. Vasantha and three daughters Lakshmi Valli Priya.^[2]

• Mehta, V. B.; Ramanathan, A. (1985), "Frobenius splitting and cohomology vanishing for Schubert varieties", Annals of Mathematics, Second Series, 122 (1): 27–40, doi:10.2307/1971368, ISSN 0003-486X, JSTOR 1971368, MR 0799251
• Ramanan, S.; Ramanathan, A. (1985), "Projective normality of flag varieties and Schubert varieties" (PDF), Inventiones Mathematicae, 79 (2): 217–224, Bibcode:1985InMat..79..217R, doi:10.1007/BF01388970, ISSN 0020-9910, MR 0778124, S2CID 123105737

• Annamalai Ramanathan citation