Carl Louis Ferdinand von Lindemann (12 April 1852 – 6 March 1939) was a German mathematician who proved 1882 that (pi) is a transcendental number, meaning it is not a root of any nonzero polynomial with rational coefficients.
Lindemann was born in Hanover, the capital of the Kingdom of Hanover. His father, Ferdinand Lindemann, taught modern languages at a gymnasium in Hanover. His mother, Emilie Crusius, was the daughter of the gymnasium's headmaster. The family later moved to Schwerin, where young Ferdinand attended school.
He studied mathematics at Göttingen, Erlangen, and Munich. At Erlangen he received a doctorate, supervised by Felix Klein, on non-Euclidean geometry. Lindemann subsequently taught in Würzburg and at the University of Freiburg. During his time in Freiburg, Lindemann devised his proof that is a transcendental number (see the LindemannâÂÂWeierstrass theorem). After his time in Freiburg, Lindemann transferred to the University of Königsberg. While a professor in Königsberg, Lindemann acted as supervisor for the doctoral theses of the mathematicians David Hilbert, Hermann Minkowski, and Arnold Sommerfeld.
In 1882, Lindemann published the result for which he is best known, the transcendence of . His methods were similar to those used nine years earlier by Charles Hermite to show that e, the base of natural logarithms, is transcendental. Before the publication of Lindemann's proof, Johann Heinrich Lambert had already shown that is irrational in 1761.