Career
He is an applied mathematician and a descendant of Carl Gauss. Welch received his Bachelor of Surgery in mathematics from the University of Illinois, 1951, and Doctor of Philosophy in mathematics from the California Institute of Technology, 1958, under advisor Frederic Bohnenblust. He worked at the Jet Propulsion Laboratory 1956–1959, Institute for Defense Analyses, 1959–1965, and University of Southern California, 1965–1999.