Das Mathematische Kolloquium ist eine gemeinsame wissenschaftliche Veranstaltung des gesamten Mathematischen Instituts. Es steht allen Interessierten offen und richtet sich neben den Mitgliedern und Mitarbeitern des Instituts auch an die Studierenden. Das Kolloquium findet dreimal im Semester am Donnerstag um 15:00 s.t. im Hörsaal II, Albertstr. 23b statt. Danach (gegen 16:15) gibt es Kaffee und Kekse, zu dem der vortragende Gast und alle Besucher eingeladen sind.
Donnerstag, 31.10.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 7.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 14.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 21.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Higher Lie groupoids
Donnerstag, 28.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Lie groupoids are a fundamental part of the language of\ndifferential geometry: they bring both differentiable actions of Lie groups\nand foliations under a single roof. In complex geometry, they underly the\nwork of Kuranishi and others on moduli of holomorphic vector bundles. In\nthis talk, I will report on recent work (joint with Kai Behrend)\ngeneralizing the theory of Lie groupoids to higher groupoids - where the\nsymmetries have symmetries of their own, and so on. We will show how this\nyields a language for extending Kuranishi's ideas to the setting of\ncomplexes of holomorphic bundles (or better, of twisted complexes).\n
Donnerstag, 5.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 12.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
On buttons and balls that cannot run away
Donnerstag, 19.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
This lecture presents convex sets of constant width. They are\ncharacterized by the fact that any two nonidentical tangent lines or tangent\nplanes have the same distance from each other, but they are not necessarily\ndiscs (in the plane) or balls (in 3-space). I will show how such sets can be\nused to drill square holes, and that the ignorance of such sets had fatal\nconsequences in the American space flight program. I shall also report on a\nlong-standing open conjecture and its recent development. The talk contains\nalso some video clips and is suitable for a general audience with\nmathematical interest.
Donnerstag, 26.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 2.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 9.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 16.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Using semigroups to study coupled cell networks
Donnerstag, 23.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Dynamical systems with a coupled cell network\nstructure arise in applications that range from statistical\nmechanics and electrical circuits to neural networks,\nsystems biology, power grids and the world wide web.\n A network structure can have a strong impact on the\nbehaviour of a dynamical system. For example, it has been\nobserved that networks can robustly exhibit (partial)\nsynchronisation, multiple eigenvalues and degenerate\nbifurcations. In this talk I will explain how semigroups\nand their representations can be used to understand and\npredict these phenomena. As an application of our theory, I\nwill discuss how a simple feed-forward motif can act as an\namplifier.\n This is joint work with Jan Sanders.
Donnerstag, 30.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 6.2.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Donnerstag, 13.2.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Montag, 3.3.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
test
Kapitalertragssteuern in zeitstetigen Finanzmarktmodellen
Mittwoch, 19.3.14, 09:00-10:00, Raum 404, Eckerstr. 1
The Skorokhod embedding problem for homogeneous diffusions and applications to stopping contests
Mittwoch, 19.3.14, 11:00-12:00, Raum 404, Eckerstr. 1
A probalistic link between stochastic processes, multivariate distributions an portfolio-credit derivatives
Mittwoch, 19.3.14, 14:00-15:00, Raum 404, Eckerstr. 1
Kreditrisiken: Modell, Risiken und neue Entwicklungen
Donnerstag, 20.3.14, 09:00-10:00, Raum 404, Eckerstr. 1
Stochastische Volatilität und mögliche Langzeitabhängigkeit: Das supOU Modell
Donnerstag, 20.3.14, 11:00-12:00, Raum 404, Eckerstr. 1
Parameterunsicherheit in der Portfoliooptimierung
Donnerstag, 20.3.14, 15:00-16:00, Raum 404, Eckerstr. 1