Günter Harder Explained

Birth Date:	14 March 1938
Birth Place:	Ratzeburg, Germany
Alma Mater:	University of Hamburg
Occupation:	University mathematics professor

Günter Harder (born 14 March 1938 in Ratzeburg) is a German mathematician, specializing in arithmetic geometry and number theory.

Education

Harder studied mathematics and physics in Hamburg and Göttingen. Simultaneously with the Staatsexamen in 1964 in Hamburg, he received his doctoral degree (Dr. rer. nat.) under Ernst Witt with a thesis Über die Galoiskohomologie der Tori. Two years later he completed his habilitation.

Career

After a one-year postdoc position at Princeton University and a position as an assistant professor at the University of Heidelberg, he became a professor ordinarius at the University of Bonn. With the exception of a six-year stay at the former Universität-Gesamthochschule Wuppertal, Harder remained at the University of Bonn until his retirement in 2003. From 1995 to 2006 he was one of the directors of the Max-Planck-Institut für Mathematik in Bonn.

He was a visiting professor at Harvard University, Yale University, at Princeton's Institute for Advanced Study (IAS) (for the academic years 1966–1967, 1972–1973, 1986–1987, autumn of 1983, autumn of 2006),^[1] at the Institut des Hautes Études Scientifiques (I.H.É.S.) in Paris, at the Tata Institute of Fundamental Research in Mumbai, and at the Mathematical Sciences Research Institute (MSRI) at the University of California, Berkeley.

For decades, Harder was known to German mathematicians as the Spiritus Rector for a mathematical workshop held for one week in spring and one week in autumn; the workshop, sponsored by the Mathematical Research Institute of Oberwolfach, introduced young mathematicians and scientists to important new developments in pure mathematics and mathematical sciences.

Harder's doctoral students include Kai Behrend, Jörg Bewersdorff, Joachim Schwermer, and Maria Heep-Altiner.

Research

His research deals with arithmetic geometry, automorphic forms, Shimura varieties, motives, and algebraic number theory. He made foundational contributions to the Waldspurger formula.

With Ina Kersten, he is a co-editor of the collected works of Ernst Witt.

Awards and honors

Harder was an invited speaker at the International Congress of Mathematicians in 1970 and gave a talk titled Semisimple group schemes over curves and automorphic functions^[2] and in 1990 with a talk titled Eisenstein cohomology of arithmetic groups and its applications to number theory.^[3] In 1988 he was awarded the Leibniz Prize by the Deutsche Forschungsgemeinschaft.

In 2004 Harder received, with Friedhelm Waldhausen, the von Staudt Prize.^[4]

Selected publications

• Harder . G. . A Gauss-Bonnet formula for discrete arithmetically defined groups . . Societe Mathematique de France . 4 . 3 . 1971 . 0012-9593 . 10.24033/asens.1217 . 409–455. free . (online).
• Harder . G. . Chevalley Groups Over Function Fields and Automorphic Forms . . JSTOR . 100 . 2 . 1974 . 249–306 . 0003-486X . 10.2307/1971073 . 1971073 .
• Harder . G. . Narasimhan . M. S. . On the cohomology groups of moduli spaces of vector bundles on curves . . Springer Science and Business Media LLC . 212 . 3 . 1975 . 0025-5831 . 10.1007/bf01357141 . 215–248. 117851906 . (online)
• Algebraische Zyklen auf Hilbert-Blumenthal-Flächen. . Journal für die reine und angewandte Mathematik (Crelle's Journal) . Walter de Gruyter GmbH . 1986 . 366 . 1 March 1986 . 0075-4102 . 10.1515/crll.1986.366.53 . 53–120 . 119657447 . . (online).
• Harder . G. . Eisenstein cohomology of arithmetic groups. The case GL2 . . Springer Science and Business Media LLC . 89 . 1 . 1987 . 0020-9910 . 10.1007/bf01404673 . 37–118. 1987InMat..89...37H . 121239087 .
• Goresky . M. . Harder . G. . MacPherson . R. . Weighted cohomology . Inventiones Mathematicae . Springer Science and Business Media LLC . 116 . 1 . 1994 . 0020-9910 . 10.1007/bf01231560 . 139–213. 1994InMat.116..139G . 189831832 .
• Book: Harder, Günter . Lecture Notes in Mathematics . Eisensteinkohomologie und die Konstruktion gemischter Motive . Springer Berlin Heidelberg . Berlin, Heidelberg . 1993 . 1562 . 978-3-540-57408-8 . 0075-8434 . 10.1007/bfb0090305.
• Book: Harder, Günter . Aspects of Mathematics . Lectures on Algebraic Geometry I . Springer Fachmedien Wiesbaden . Wiesbaden . 2011 . 35 . 978-3-8348-1844-7 . 0179-2156 . 10.1007/978-3-8348-8330-8.
• Book: Harder, Günter . Lectures on Algebraic Geometry II . Vieweg+Teubner . Wiesbaden . 2011 . 978-3-8348-0432-7 . 10.1007/978-3-8348-8159-5.
• Book: Bruinier, Jan . The 1-2-3 of modular forms : lectures at a summer school in Nordfjordeid, Norway . Springer . Berlin . 2008 . 978-3-540-74117-6 . 233973403. ^[5] (contains Harder's contribution: Book: Harder, Günter . The 1-2-3 of Modular Forms . Congruence Between a Siegel and an Elliptic Modular Form . Springer Berlin Heidelberg . Berlin, Heidelberg . 2008 . 247–262 . 10.1007/978-3-540-74119-0_4. 978-3-540-74117-6 .)

External links

• Homepage of Günter Harder at the Hausdorff Center of the University of Bonn
• Homepage of Günter Harder at the University of Bonn

Notes and References

1. Web site: Günter Harder – Scholars | Institute for Advanced Study. 9 December 2019. www.ias.edu. 16 December 2021.
2. Harder, Günter, "Semisimple group schemes over curves and automorphic functions." Actes, Congrès intern. Math. Tome 2 (1970): 307–312.
3. Harder, Günter. "Eisenstein cohomology of arithmetic groups and its applications to number theory." In Proceedings of the International Congress of Mathematicians, vol. 1, pp. 779–790. 1990.
4. Web site: Günter Harder | Max Planck Institute for Mathematics. www.mpim-bonn.mpg.de. 16 December 2021.
5. Folsom . Amanda . Book Review: The 1-2-3 of modular forms . . American Mathematical Society (AMS) . 46 . 3 . 23 March 2009 . 0273-0979 . 10.1090/s0273-0979-09-01256-7 . 527–533. free .