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
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Ballmann earned his doctorate from the University of Bonn in 1979, under the supervision of Wilhelm Klingenberg.[1] He currently is a professor at the University of Bonn, and the managing director of the Max Planck Institute for Mathematics in Bonn, Germany, since 2007.[2] He has advised 16 doctoral students at Bonn, including Christian Bär and Anna Wienhard.[1]
He is a member of the German Academy of Sciences Leopoldina since 2007,[3] and a member of the scientific committee of the Mathematical Research Institute of Oberwolfach since 2004.
Selected works
- Lectures on spaces of non positive curvatures (PDF; 818 kB), DMV Seminar, Birkhäuser 1995
- Spaces of non positive curvature, Jahresbericht DMV, vol. 103, 2001, pp. 52–65
- Der Satz von Lusternik und Schnirelmann, Bonner Mathematische Schriften, vol. 102, 1978, pp. 1–25
- Ballmann, Werner; Thorbergsson, Gudlaugur; Ziller, Wolfgang (1982). "Closed geodesics on positively curved manifolds". Annals of Mathematics. 116 (2): 213–247. doi:10.2307/2007062. JSTOR 2007062. MR 0672836.
- Ballmann, Werner (1985). "Nonpositively Curved Manifolds of Higher Rank". The Annals of Mathematics. JSTOR. 122 (3): 597–609. doi:10.2307/1971331. ISSN 0003-486X. JSTOR 1971331.
- with M. Brin: Orbihedra of nonpositive curvature. Publications Mathématiques de l'IHÉS No. 82 (1995), 169–209 (1996).
- Ballmann, Werner; Światkowski, Jacek (1997). "On -cohomology and property (T) for automorphism groups of polyhedral cell complexes". Geometric and Functional Analysis. 7 (4): 615–645. doi:10.1007/s000390050022. MR 1465598. S2CID 15531550.
References
- Hans Werner Ballmann at the Mathematics Genealogy Project
- "Werner Ballmann". Max Planck Institute for Mathematics. Retrieved 17 December 2021.
- "Mitglieder". Nationale Akademie der Wissenschaften Leopoldina (in German). 25 September 2021. Retrieved 17 December 2021.