Stefan Kaczmarz

Stefan Marian Kaczmarz, born on 20 March 1895, was a Polish mathematician and a representative of the Lwow School of Mathematics. He was a professor of mathematics in the faculty of mechanical engineering of Jan Kazimierz University of Lwow from 1923 to 1939, where he collaborated with Stefan Banach, and he is recorded as dying in 1939. He is known for introducing the Kaczmarz method, an iterative algorithm for solving systems of linear equations that was rediscovered in 1970 for image reconstruction from projections, where it is called the Algebraic Reconstruction Technique. That rediscovery gave the method its place as the basis of many modern imaging technologies, including the computed tomography scan. This entry treats him as the originator of that algorithm; his other mathematical work belongs to the mathematics atlas.