The department is pleased to welcome our next colloquium speaker,** David Saltman**, from the Center for Communications Research.

**Title:** Breaking the Enigma the First Time

**Date:** Wednesday, February 27, 2019, 11:00 am

**Location:** SCP 317

**Abstract: **“Enigma” is our name for a German secret coding machine used extensively in World War Two. It is well known that it was “broken”, meaning that the Allies could read messages, at Bletchley Park. However, Enigma was first broken by the Poles, who made use of weaknesses in the machine and the protocols the Germans first followed in using the Enigma. We will discuss the machine, the mathematics behind the Polish success, and how important that success was. As part of the talk, I will invite you to examine and operate a original Enigma machine.

**Biography:** David J. Saltman has been the Director of the Center for Communications Research in Princeton, NJ, since 2007. Before his directorship, Dr. Saltman participated in several SCAMPs – the summer programs hosted by IDA’s research centers to resolve really tough problems, sometimes with remarkable success – since 1994. Dr. Saltman was formerly the Mildred Caldell and Baine Perkins Kerr Centennial Professor of mathematics at the University of Texas, Austin. His work has included studying Noether’s Problem and showing the relation to Galois theory, and giving the first counterexample to this problem over an algebraically closed field. He has studied the so-called universal division algebra, proven it retract rational for prime degrees, and constructed the first non-crossed product p algebra. He invented unramified Galois cohomology and studied the degree 3 case and the relation to the universal division algebra. Outside of pure research, he served as algebra editor and managing editor of the Transactions of Mathematics. He also is involved in mathematics education, participating, for example, in a Vertical Teams AP Calculus Project. Dr. Saltman received his Ph.D. in 1976 from Yale University and worked at both the University of Chicago and Yale before joining the University of Texas in 1982.