Aleksandr Lyapunov
Mathematician
Russian applied mathematics expert who played a key role in the development of the stability theory of a dynamical system. He was also a respected professor at Kharkiv University.
He studied mathematics at the University of Saint Petersburg and Kharkiv University.
He was a corresponding member of the Academy of Sciences in Paris.
His brother Sergei was a well-known composer.
His theories were studied by later applied mathematics experts like Dennis Ritchie.