was born in Detroit, Michigan.
He is a Senior Professor in the Faculty of Mathematics at the University of Duisburg-Essen.
He works in algebraic geometry and algebraic topology, specialising in motivic cohomology, algebraic K-theory, algebraic cobordism, motives and motivic homotopy theory, with an interest in applications to basic problems in algebraic geometry and arithmetics.
He is a member of the Leopoldina-German National Academy of Science and the Academia Europaea, and is a recipient of the Wolfgang Paul Award (2001) and the Senior Berwick Prize (2018). He also held a Humboldt Professorship at the University of Duisburg-Essen (2009-2014).