Hans Werner Ballmann

Hans Werner Ballmann (known as Werner Ballmann; born 11 April 1951) is a German mathematician. His area of research is differential geometry with focus on geodesic flows, spaces of negative curvature as well as spectral theory of Dirac operators

Ballmann earned his doctorate from the University of Bonn in 1979, under the supervision of Wilhelm Klingenberg. He was a professor at the University of Bonn, and a director of the Max Planck Institute for Mathematics in Bonn, Germany, from 2007 to 2019. He has advised 16 doctoral students at Bonn, including Christian Bär and Anna Wienhard.

He is a member of the German Academy of Sciences Leopoldina since 2007, and a member of the scientific committee of the Mathematical Research Institute of Oberwolfach since 2004. Provided by Wikipedia