Professor S. (Sundararaman) Ramanan (born 20 July 1937) is an Indian mathematician who works in the area of algebraic geometry, moduli spaces and Lie groups.[1] He completed his Ph. D. at the Tata Institute of Fundamental Research, under the direction of M. S. Narasimhan, with whom he collaborated for decades. He later pursued a lengthy career at TIFR, with many international visits. He picked up the methods of modern differential geometry from the French mathematician Jean-Louis Koszul,[2] and later successfully applied it for his research centered around algebraic geometry. He has also made important contributions to the topics of abelian varieties and also vector bundles.
He was a senior colleague of M. S. Raghunathan and influenced him considerably.[3] Vijay Kumar Patodi who proved part of the Atiyah-Singer index theorem, was found and encouraged by Ramanan, and Patodi's Ph. D. was done under the combined direction of Narasimhan and Ramanan.[4] He has a considerable number of students. Mathematicians influenced by Ramanan include M. Mohan Kumar,[5] Shrawan Kumar,[6] D. S. Nagaraj,[7] Kapil H. Paranjape,[8] Jaya Iyer[9] and several others.[10] He was very close to, and has closely collaborated with, many western mathematicians of note, like Raoul Bott. While in TIFR as distinguished professor, he was one of the important figures in the school of mathematics in India. He now continues his contributions via teaching at the Chennai Mathematical Institute,[11] where he is adjunct professor. He is a great lecturer[12] and expositor, and has written a graduate level book on Global Calculus.[13] His daughter Kavita Ramanan[14] is also a mathematician.
The honors awarded to prof. Ramanan include the Shanti Swarup Bhatnagar Prize[15] in 1979. He is an alumnus of the Vivekananda College in Chennai.