Veranstaltungsübersicht -- Wintersemester 2013/2014 (Archiv)

Montag,
2013-10-21
16:15 Uhr
Raum 404, Eckerstr. 1
NN: Programmdiskussion
Montag,
2013-11-04
16:15 Uhr
Raum 404, Eckerstr. 1
Patrick Emmerich: Conformally flat cylinders without conjugate points

For surfaces without conjugate points, Eberhard Hopf's method leads to optimal rigidity results. The question arises of whether (a generalization of) the method is equally powerful in higher dimensions. We will investigate the case of conformally flat cylinders.

Montag,
2013-11-11
16:15 Uhr
Raum 404, Eckerstr. 1
Nena Röttgen: Trapped Reeb orbits do not imply periodic ones
Montag,
2013-11-18
16:15 Uhr
Raum 404, Eckerstr. 1
Johanna Andrae: Euler Structures on Fibre Bundles
Montag,
2013-11-25
16:15 Uhr
Raum 404, Eckerstr. 1
Christian Ketterer: Cones over metric measure spaces and the maximal diameter theorem
"Vortrag im Rahmen des SFB TR 71"

We briefly describe the definition of curvature-dimension bounds in the sense of Lott-Villani/Sturm (CD(K,N)) and recent results about Riemannian differential calculus for metric measure spaces. Then we present the following theorem: the cone over a metric measure space satisfies CD(KN,N-1) if and only if the underlying space satisfies CD(N-1,N). As consequence of this result and the Cheeger-Gigli-Gromoll splitting theorem we obtain a maximal diameter theorem in the context of metric measure spaces.

Montag,
2013-12-02
16:15 Uhr
Raum 404, Eckerstr. 1
Anda Degeratu: The Kähler-Einstein problem

This will be an overview of the Kähler-Einstein problem, including its very recent resolution in the positive case.

Montag,
2013-12-09
16:00-18:00 Uhr
Raum 404, Eckerstr. 1
Arkadi Schelling: A universal eta-Invariant for G2-Structures
Talk on my Diploma Thesis

In this talk I will give a short introduction to the exceptional Lie-group G2. Then I will motivate G2-structure with G2-manifolds, i. e. Riemannian manifolds with holonomy group G2, that are an exceptional case in the classification of Berger and allegedly have applications in physics. On these G2-structures Crowley and Nordström defined the nu-invariant with values in Z/48Z, which I will explain. The mod 3 reduction of the nu-invariant is a G2-bordism invariant and has been interpreted as a universal eta-invariant in my thesis.

Montag,
2013-12-09
16:15 Uhr
Raum 404, Eckerstr. 1
Arkadi Schelling: tba
Montag,
2013-12-16
16:15-17:45 Uhr
Raum 404, Eckerstr. 1
Yi-Sheng Wang: Algebraic K-theory, eta-invariant and homology sphere

In this talk we will discuss how to use eta-invariant to find some geometric models for some algebraic K-groups.

Montag,
2014-01-13
16:15-17:45 Uhr
Raum 404, Eckerstr. 1
Florian Beck: Some simple singularity theory
This talk reviews some basics of singularity theory in the complex analytic setting. Towards the end we will have a closer look at so-called simple singularities.
Montag,
2014-01-20
16:15-17:45 Uhr
Raum 404, Eckerstr. 1
Oliver Gray (Bristol): Classifying superconformal field theories via chiral rings

I will introduce some of the main mathematical ideas behind N=2 superconformal field theory, using the N=2 minimal models as a concrete example, and explore some of their connections to geometry.

To illustrate these ideas I will focus on the so-called "chiral rings", which arise from basic Lie algebra representation theory plus ideas from quantum field theory. I show how the chiral rings relate to Calabi-Yau geometry, then I'll describe how chiral rings appear in Cecotti and Vafa's famous ADE singularity classification of a special subclass of N=2 minimal models (those with "space-time supersymmetry"), and we'll briefly reacquaint ourselves with some other prominent appearances the ADE pattern in maths and physics.

Finally I'll present the chiral rings of the entire class of N=2 minimal models (when the extra assumption of space-time supersymmetry is dropped) and report on ongoing work with K. Wendland concerning a geometric classification of these theories.

Montag,
2014-01-27
16:15 Uhr
Raum 404, Eckerstr. 1
Nora Hänle: Complex multiplication on abelian varieties
Montag,
2014-02-03
16:15 Uhr
Raum 404, Eckerstr. 1
Nora Hänle: tba
Montag,
2014-02-03
16:15 Uhr
Raum 404, Eckerstr. 1
Anja Fuchshuber: Eta-forms in family index theory

This talk will give a short introduction how the differential of the eta form gives the difference between the cohomological and the analytical index. Then we'll look at an example where the dimension of the kernel of the Dirac operator changes and see how this affects the eta-form.

Montag,
2014-02-17
10:15-11:15 Uhr
Raum 404, Eckerstr. 1
Andreas Ott (Cambridge): Bounded cohomology via partial differential equations

By the van Est isomorphism, continuous cohomology of simple Lie groups vanishes in degree greater than the dimension of the associated symmetric space. Monod conjectured that a similar vanishing theorem should hold for continuous bounded cohomology. In this talk, we will present a new technique that employs partial differential equations in order to explicitly construct primitives in the continuous bounded cohomology of Lie groups. As an application, we prove Monod's conjecture for SL(2,R) in degree four and discuss perturbations of the Spence-Abel functional equation for the dilogarithm function. This is joint work with Tobias Hartnick.

Dienstag,
2014-02-18
10:15-11:15 Uhr
Raum 404, Eckerstr. 1
Jan Swoboda (MPI Bonn): The asymptotic geometry of the moduli space of Higgs bundles over a Riemann surface
Siehe auch: http://home.mathematik.uni-freiburg.de/goette/Swoboda.pdf
Freitag,
2014-02-21
10:15-11:15 Uhr
Raum 404, Eckerstr. 1
Robert Schmidt (LMU München): Coarse topology of leaves of foliations
Siehe auch: http://home.mathematik.uni-freiburg.de/goette/Schmidt.pdf

Abonnieren

Die Einträge dieser Veranstaltung können im iCalender Format abonniert werden. die URL dazu lautet:
http://wochenprogramm.mathematik.uni-freiburg.de/ical/WS2013-2014/OS-DiffGeo.ics