Oberseminar Geometrie, Topologie und Analysis

S. Friedl, H. Geiges, G. Marinescu, G. Thorbergsson

Wintersemester 2011/12

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

28.10.11 Kai Zehmisch
Die Weinstein-Vermutung für Kotangentialbündel

Zusammenfassung: In der Klassischen Mechanik studiert man die Bewegungsgleichungen von festen Körpern. Weinstein vermutete 1979, daß sich unter gewissen natürlichen geometrischen Bedingungen an die Energiehyperflächen stets geschlossene Bahnen finden lassen. In meinem Vortrag möchte ich über eine gemeinsame Arbeit mit H. Geiges berichten, in der wir die Weinstein-Vermutung für eine große Klasse von Kotangentialbündeln verifizieren.
11.11.11 R. İnanç Baykur (MPI Bonn)
Round handles and smooth four-manifolds

Abstract: In this talk, we are going to unfold the strong affiliation of round handles with smooth four-manifolds. Various fundamental topics that appear in the study of four-manifolds, such as handlebodies, cobordisms, logarithmic transforms along tori, exotic smooth structures, and broken Lefschetz brations, will come into play as we discuss the relevant interactions between them.
25.11.11 Ionut Chiose (IMAR, Bukarest)
On the Kähler rank of compact complex surfaces

Abstract: The Kähler rank of compact complex surfaces was introduced by Harvey and Lawson in their 1983 paper on Kähler manifolds as a measure of "kählerness". We classify the compact complex surfaces of Kähler rank 1. These are either elliptic surfaces, Hopf surfaces, or they admit a holomorphic foliation of a very special type.
20.1.12 Karl Friedrich Siburg (TU Dortmund)
Dynamik von Magnetfeldern

27.1.12 Johan Taflin (Oslo)
Equidistribution speed towards the Green current in codimension 1

Abstract: To a holomorphic endomorphism f of the complex projective space, we can associate its Green current T. It is a positive closed current of bidegree (1,1) whose support is the Julia set of f and which gives several information on the dynamics. In particular, for a hypersurface H, generic in the Zariski sense, we give an explicit speed of convergence of the pull-backs of H by the iterates f n towards T.

H. Geiges, 5.4.02