births
April 5, 1869
Sergey Chaplygin, Russian physicist, mathematician, and engineer (died 1942)
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.