Sophus Lie (December 17, 1842 – February 18, 1899) was a Norwegian mathematician who founded the theory of continuous symmetry, known as Lie groups and Lie algebras. His work profoundly influenced mathematics and theoretical physics, especially in differential equations, geometry, and quantum mechanics. Born in Nærøy, Norway, Lie studied at the University of Christiania (now Oslo) and later in Berlin and Paris. He collaborated with Felix Klein on transformation groups. Lie groups and Lie algebras are now essential tools for describing continuous symmetries in modern science. Despite health issues, he continued research until his death. His contributions are recognized as among the greatest in 19th-century mathematics.
