Thoralf Skolem

Thoralf Albert Skolem (23 May 1887 – 23 March 1963) was a Norwegian mathematician who made significant contributions to mathematical logic, set theory, and number theory. Born in Sandsvær, Norway, he passed his university entrance examinations in 1905 and began studying mathematics at Det Kongelige Frederiks Universitet. His early work included physics papers co-authored with Kristian Birkeland. Skolem's doctoral dissertation, completed in 1913, was on the algebra of logic. He furthered his studies in mathematical logic at the University of Göttingen. He held positions at Det Kongelige Frederiks Universitet and later at the Chr. Michelsen Institute before returning to a professorship at the University of Oslo. Skolem is credited with refining set theory axioms and proving the Löwenheim–Skolem theorem, which he simplified from Leopold Löwenheim's earlier work. He also anticipated Gödel's incompleteness theorems and developed primitive recursive arithmetic, laying groundwork for theoretical computer science. He served as president of the Norwegian Mathematical Society and edited its journal. After retiring in 1957, he continued to be intellectually active and made trips to the United States.