Oberseminar Geometrie, Topologie und Analysis

H. Geiges, G. Marinescu, U. Semmelmann, G. Thorbergsson

Sommersemester 2009

Freitag, 10:30-11:30, Seminarraum 1



15.5.09 Dr. William Kirwin (MPI Leipzig)
Lagrangian fibrations of coadjoint orbits from the Iwasawa decomposition

22.5.09 Prof. Krishnan Shankar (University of Oklahoma, z.Zt. Münster)
Riemannian submersions from compact Lie groups

Abstract: We construct infinitely many examples of Riemannian submersions GM, where G is a simple, compact Lie group, M is a smooth Riemannian manifold and such that M is not a quotient of G by any group U ⊆ Diff(G) acting freely on G. This is joint work with Martin Kerin.
29.5.09 Prof. Viktor Schroeder (Universität Zürich)
Ptolemy spaces

Abstract: A metric space (X,d) is called a Ptolemy space if for any quadrupels of points x,y,z,w in X the three numbers d(x,y)d(z,w), d(x,z)d(y,w) and d(x,w)d(y,z) satisfy the triangle inequality. Ptolemy spaces arise naturally if one studies the ideal boundary of a noncompact simply connected manifold of negative curvature or more generally CAT(-1) spaces. We give an introduction to the geometry of these spaces with applications to manifolds of negative curvature.
12.6.09 Dr. Chin-Yu Hsiao (Göteborg)
On the singularities of the Bergman kernel

Abstract: In this work, we obtain the full asymptotic expansion of the Bergman projection for (0,q)-forms when the Levi form is non-degenerate. This generalizes a result of Boutet de Monvel and Sjöstrand for (0,0)-forms. We will explain our method in an elementary fashion. We hope that this talk can serve as an introduction to certain microlocal techniques with applications in complex analysis.
19.6.09
10:30-12:00
Prof. András Stipsicz (Budapest)
Heegaard Floer invariants in contact topology

Abstract:This is the second lecture in a loosely connected series of three lectures. See this separate announcement.
26.6.09
10:30-12:00
Prof. András Stipsicz (Budapest)
Surface singularities with rational homology disk smoothings

10.7.09 Prof. Wolfgang Ziller (University of Pennsylvania)
Positive Schnittkrümmung: Beispiele und Hindernisse in Faserbündeln



H. Geiges, 5.4.02