19.10.07	Prof. Dr. Bernd Siebert (Freiburg) Die Geometrie des Spiegelsymmetrie-Phänomens
26.10.07	Prof. Dr. Kai Köhler (Düsseldorf) Quaternionic torsion and arithmetic algebraic geometry
9.11.07	Prof. Dr. Ilka Agricola (HU Berlin) Riemannsche Mannigfaltigkeiten mit Torsion und Dirac-Operatoren
30.11.07	Dr. Anda Degeratu (MPI Golm) Fredholm results for elliptic operators on quasi-asymptotically conical (QAC) spaces Abstract: A Calabi-Yau orbifold is locally modeled on Cn/G with G a finite subgroup of SU(n). If the singularity is isolated, then the crepant resolution (if it exists) is an ALE manifold, for which index-type results are well known. However, most of the time the singularity is not isolated, and for the corresponding crepant resolution there is no index theorem so far. In this talk, I present the first step towards obtaining such a result: I will introduce the class of iterated cone-edge singular manifolds and the corresponding quasi-asymptotically conical spaces (for which orbifolds and their crepant resolutions are an example), and build-up the general set-up for studying Fredholm properties of geometrical elliptic operators on these spaces. This is work in progress with Rafe Mazzeo.
7.12.07	Prof. Dr. Patrick Popescu-Pampu (Paris VII) The geometry of continued fractions and the topology of surface singularities Abstract: I will survey the use of continued fractions in the algebraic and topological study of complex curve and surface singularities. I will show how a geometric duality between supplementary cones in a plane endowed with a lattice allows one to explain all the numerical symmetries met during the survey.
14.12.07	Prof. Dr. Helga Baum (HU Berlin) Conformal manifolds with special unitary holonomy
11.1.08	Dr. Bernhard Hanke (LMU München) Grobgeometrie und positive Skalarkrümmung Zusammenfassung: Bekanntlich besitzen geschlossene Spinmannigfaltigkeiten, deren Â-Geschlecht nicht verschwindet, keine Riemannsche Metrik positiver Skalarkrümmung. Dies impliziert, daß die universelle Überlagerung einer solchen Mannigfaltigkeit keine Metrik positiver Skalarkrümmung trägt, für die die Decktransformationsgruppe isometrisch operiert. Wir untersuchen die Frage, wann die universelle Überlagerung eine positive Skalarkrümmungsmetrik trägt, für die die Decktransformationsgruppe quasi-isometrisch operiert.
18.1.08	Prof. Dr. Dorothee Schüth (HU Berlin) Lokale spektrale Starrheit von biinvarianten Metriken auf kompakten Lie-Gruppen
25.1.08	Dr. Alexander Lytchak (Bonn) Geometric resolutions of isometric actions

H. Geiges, 5.4.02