Sergey Chaplygin

Sergey Alexeyevich Chaplygin was a Russian and Soviet physicist, mathematician, and mechanical engineer. He is known for mathematical formulas such as Chaplygin's equation and for a hypothetical substance in cosmology called Chaplygin gas, named after him.

5 April 1869

Born on the same birth date (5 April 1869): Albert Roussel

Born on the same birth day (5 April): Anton Kokorin • Asteris Koutoulas • Chen Yanqing • Daniel Schneidermann • Frank Schepke • Haidar Abu Bakr al-Attas • Ian Redford (footballer) • Janet Rowley • Laura Feiersinger • Liemarvin Bonevacia • Pierre Nihant • Richard Eberhart • Robert Bloch • Roman Steinberg • Samuel Cate Prescott • Shikha Uberoi

Born in the same month (April 1869): Albert Roussel • Gustav Vigeland • Hans Poelzig • Harvey Cushing • Henri Désiré Landru • Hughie Jennings • Levon Shant • Mary Colter