W.H. Gottschalk

Walter Helbig Gottschalk (1918–2004) was an American mathematician and one of the founders of topological dynamics. He earned his Ph.D. from the University of Virginia in 1944 under Gustav Hedlund and held faculty positions at the University of Pennsylvania and Wesleyan University. He is best known for co-authoring the seminal 1955 monograph Topological Dynamics and for originating the study of surjunctive groups, which later motivated the sofic groups conjecture.