Biography
Kollagunta Gopalaiyer Ramanathan, Indian mathematician (Hyderabad 13 November 1920 – Bombay 10 May 1992)
Gained international recognition for his researches on analytic theory of quadratic forms, modular functions and discontinuous groups
Obtained a formula for the discriminant of a division algebra
Solved the problem of constructing infinitely many classes of mutually incommensurable discrete groups of the first kind in classical semisimple groups
Proved that complete space-like submanifolds with parallel mean curvature vector in a De Sitter space are totally umbilical independent of K. Akutagawa & Q.M. Cheng
