Ralph Louis Cohen

[1] Cohen received his bachelor's degree from the University of Michigan in 1973 and his Ph.D. in 1978 from Brandeis University where he worked under the supervision of Edgar H. Brown, Jr. His thesis was titled On Odd Primary Stable Homotopy Theory.

Cohen is now the Barbara Kimball Browning Professor of Mathematics at Stanford.

Cohen has been the Ph.D. supervisor to over 30 doctoral students, including Ulrike Tillmann and Ernesto Lupercio.

In 1991, Cohen, together with Frederick Cohen, Benjamin Mann, and R. James Milgram gave a complete description of the algebraic topology of the space of rational functions, and in the following years he made several contributions to the study of related moduli spaces.

Since 2002 Cohen has been one of the developers and contributors to the theory of String topology, which was introduced originally by Moira Chas and Dennis Sullivan.