Kathrin Bringmann

Kathrin Bringmann
Name	Kathrin Bringmann
Birth date	1977
Birth place	Oldenburg, Germany
Nationality	German
Fields	Number theory, Modular forms, Mock theta functions
Alma mater	University of Hamburg
Doctoral advisor	Winfried Kohnen
Known for	Mock theta functions, Maass forms, q-series
Awards	Ostrowski Prize, Gottfried Wilhelm Leibniz Prize

Kathrin Bringmann is a German mathematician known for contributions to analytic number theory, especially the theory of mock theta functions, harmonic Maass forms, and q-series. Her work connects classical problems of Srinivasa Ramanujan with modern developments in the theories of modular forms, partitions, and mathematical physics. She has held research and faculty positions at leading institutions and has received several prestigious awards for mathematical research.

Early life and education

Bringmann was born in Oldenburg and raised in northern Germany, where she attended secondary school and developed interests that led to studies in mathematics at the University of Hamburg, University of Göttingen, and related German research centers. She completed her Diplom and then earned a Ph.D. under the supervision of Winfried Kohnen at the University of Hamburg with a dissertation focused on harmonic weak Maass forms and q-series. During her doctoral and postdoctoral years she worked in environments connected to the Max Planck Institute for Mathematics, the Institute for Advanced Study, and collaborations involving researchers from institutions such as the University of Cologne, University of Bonn, and University of Marburg.

Academic career and positions

After her Ph.D., Bringmann held postdoctoral positions and visiting appointments at institutions including the University of Minnesota, the California Institute of Technology, and the National University of Singapore before securing faculty roles. She has served as a full professor at the University of Cologne and held joint affiliations with research institutes such as the Hausdorff Center for Mathematics and the Sonderforschungsbereich networks. Bringmann has been a visiting professor at the University of Michigan, the University of Toronto, and research centers like the Mathematical Sciences Research Institute and the Institute for Pure and Applied Mathematics.

Research contributions and notable results

Bringmann's research focuses on mock theta functions first studied by Srinivasa Ramanujan, harmonic Maass forms related to work of Hans Maass, and applications to partition theory originally developed by Freeman Dyson and George Andrews. She proved exact formulas and asymptotic expansions for coefficients of mock theta functions and for partition ranks and cranks, connecting classical q-series identities of Ramanujan and G. N. Watson to modern automorphic techniques influenced by Don Zagier and Ken Ono. Her collaborations with Ken Ono, Jan Manschot, Larry Rolen, and Jeremy Lovejoy produced results on the algebraic and arithmetic properties of Maass-Poincaré series, the congruences for partition functions studied by Ramanujan and A. O. L. Atkin, and applications to quantum modular forms linked to work of Zagier and Duke, Imamoḡlu, and Tóth.

Bringmann developed methods to construct harmonic Maass forms with prescribed singularities, extending earlier constructions by R. A. Rankin and P. Deligne, and used these to obtain exact formulas for Fourier coefficients via spectral theory and the Hardy–Ramanujan–Rademacher circle method refined in contexts studied by Hans Rademacher and G. H. Hardy. Her research has produced connections between mock modular forms and Mathieu group M24 moonshine phenomena explored by Terry Gannon and John Duncan, and has informed interactions between number theory and theoretical physics topics like black hole entropy calculations investigated by Strominger and Vafa and modularity in conformal field theory studied by Edward Witten.

Awards and honors

Bringmann's achievements have been recognized with major awards including the Ostrowski Prize and the Gottfried Wilhelm Leibniz Prize. She has received fellowships and prizes such as the Sloan Research Fellowship, national research grants from organizations like the Deutsche Forschungsgemeinschaft, and invitations to deliver plenary addresses at meetings of the International Congress of Mathematicians-related conferences, the European Congress of Mathematics, and symposia organized by the American Mathematical Society and the London Mathematical Society.

Selected publications

- Bringmann, K.; Ono, K. "The f(q) mock theta function conjecture and partition ranks", Annals of Mathematics. - Bringmann, K.; Lovejoy, J. "Overpartition ranks and modular forms", Journal of Number Theory. - Bringmann, K.; Rolen, L. "Harmonic Maass forms and their applications", Transactions of the American Mathematical Society. - Bringmann, K.; Ono, K.; Rolen, L. "Asymptotics for mock theta functions and applications", Inventiones Mathematicae. - Bringmann, K.; Manschot, J.; Ono, K. "Eulerian series, Maass forms, and black hole microstates", Communications in Number Theory and Physics.

Teaching and mentoring

Bringmann has supervised doctoral students and postdoctoral researchers who have gone on to positions at institutions including the University of Cambridge, Princeton University, ETH Zurich, and research groups at the Max Planck Institute for Mathematics in the Sciences. She teaches advanced graduate courses on topics tied to modular forms, analytic number theory, and q-series, often organizing seminars in collaboration with centers such as the Hausdorff Center for Mathematics and the Institute for Advanced Study.

Outreach and professional service

Bringmann is active in the mathematical community through editorial roles for journals in number theory and modular forms, program committees for conferences organized by the European Mathematical Society and the American Mathematical Society, and outreach lectures for institutions including the Max Planck Society and public lecture series at the Hausdorff Center for Mathematics. She has chaired panels for funding bodies like the Deutsche Forschungsgemeinschaft and served on prize committees for awards administered by the German Mathematical Society and international mathematical organizations.

Category:German mathematicians Category:Number theorists Category:1977 births Category:Living people