Ramachandran Balasubramanian (born 15 March 1951) is an Indian mathematician and was Director of the Institute of Mathematical Sciences in Chennai, India. He is known for his work in number theory, which includes settling the final g(4) case of Waring's problem in 1986. He is also known for his work in Cryptography which includes his famous work with Koblitz, now commonly called the Balu-Koblitz Theorem. His work in Additive Combinatorics includes his two page paper on additive complements of squares, hence disproving a long standing conjecture of Erdős. His works on moments of Riemann zeta function is highly appreciated and he was a plenary speaker from India at ICM in 2010. He was a visiting scholar at the Institute for Advanced Study in 1980-81. He was a student of K. Ramachandra, a lifelong collaborator of Jean-Marc Deshouillers, and co-authored stellar mathematicians like Ram Murty, Kumar Murty, Heath-Brown, N. Koblitz and F. Luca. He was the founder and remains a member of the advisory board of the Hardy-Ramanujan Journal.

Awards and honours

He has received the following awards: