FB 6 Mathematik/Informatik/Physik

Institut für Mathematik


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Kolloquium

14.06.2023 um 16:15 Uhr in Raum 69/125

Prof. Dr. Kathlén Kohn (KTH Stockholm)

3D-Rekonstruktion aus Bildern und Algebraische Geometrie

Dieser Vortrag ist eine Einführung in die Rekonstruktion von 3D-Szenen aus vielen Bildern. Wir modellieren dieses Problem mit projektiver Geometrie und zeigen, dass es im Wesentlichen äquivalent zum Lösen gewisser polynomieller Gleichungssysteme ist.

21.06.2023 um 17:15 Uhr in Raum 69/125

Prof. Mihyun Kang, Ph.D. (TU Graz)

Supercritical Percolation on the Hypercube

We consider a random subgraph obtained by bond percolation on the hypercube in the supercritical regime and derive expansion properties of its giant component. As a consequence we obtain upper bounds on the diameter of the giant component and the mixing time of the lazy simple random walk on the giant component. We also extend the results to random subgraphs of high-dimensional product graphs. This talk is based on joint work with Sahar Diskin, Joshua Erde, and Michael Krivelevich.

Oberseminar Angewandte Analysis

Oberseminar Stochastik

Oberseminar Algebra

20.06.2023 um 14:15 Uhr in 32/372

Sophie Rehberg (FU Berlin)

TBA

13.06.2023 um 14:15 Uhr in 32/372

Holger Brenner (Universität Osnabrück)

Some remarks on a Theorem of Steinberg in invariant theory
A theorem of Steinberg states that the invariant ring for a finite group acting linearly on a polynominal ring is itself a polynominal ring if and only if the colenght of the Hilbert ideal equals the cardinality of the group. Here, we consider more generally the corresponding ratio between this colenght and the cardinality and show that this ratio depends only on the invariant ring. In particular, this provides a new proof of Steinberg´s theorem. Our approach uses reduction to positive characteristic and Hilbert- Kunz multiplicity in positive characteristic. This is joint work with Mandira Mondal. 

Oberseminar Topologie

Osnabrücker Maryam Mirzakhani Lecture