Joseph Kruskal

Joseph Bernard Kruskal ( born January 29, 1928 in New York City; † 19 September 2010 in Princeton (New Jersey) ) was an American mathematician and statistician.

He studied at the University of Chicago and Princeton University, where he received his doctorate in 1954 with a thesis on Theory of Well - Quasi - Ordering under Roger Lyndon and Paul Erdős.

After teaching at Princeton University and the University of Wisconsin, he was appointed assistant professor at the University of Michigan in 1958. The following year he moved to the Bell Telephone Laboratories. He was still a visiting professor at Yale, Columbia and Rutgers.

From him the Kruskal algorithm is derived for the calculation of minimum spanning trees in graph theory.

In 1960 he proved a theorem named after him on the organization properties of an infinite sequence of finite trees. In the 1980s, Harvey Friedman showed that a variant of the theorem is undecidable in Peano arithmetic.

His brothers Martin Kruskal and William Kruskal were also mathematicians.