Mittagsseminar zur Arithmetik: Zhixiang Wu (Münster): On finite presentations of supersingular representations of GL2
Tuesday, 31.01.2023 10:15 im Raum SRZ 216/217
Irreducible smooth representations of GL2(F) over characteristic p fields, where F is a finite extension of Qp, are classified up to supersingular representations. Understanding supersingular representations of GL2(Qp) was one of the first steps towards the mod p and p-adic local Langlands correspondence for GL2(Qp). However, the study of supersingular representations becomes more difficult when we change Qp to general F. In this talk, I will talk about a negative result that supersingular representations of GL2(F) are not of finite presentation whenever F is not Qp.
Angelegt am Monday, 30.01.2023 09:45 von harenbrh
Geändert am Monday, 30.01.2023 09:45 von harenbrh
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Silke Glas (University of Twente): Symplectic Model Reduction for Hamiltonian Systems
Wednesday, 01.02.2023 14:00 im Raum M5
In the beginning of this talk, we introduce the concept of model order reduction and provide a short overview of the field. Then, we consider so-called classical linear-subspace reduced order models (ROMs) and explain the necessary steps to arrive at such a model. Moreover, as we are dealing with Hamiltonian systems, it is crucial that we ensure that the underlying physical (here: symplectic) structure is preserved in the reduced model.
In the second part of the talk, we consider problems, where classical linear-subspace ROMs of low dimension might yield inaccurate results. This could be the case for certain transport-dominated problems. Thus, the reduced space needs to be extended to more general nonlinear manifolds. To this end, we provide a novel projection technique called symplectic manifold Galerkin. We derive analytical results such as stability, energy-preservation and a rigorous a-posteriori error bound. Furthermore, we provide methods to computationally approximate the nonlinear symplectic trial manifold and numerically demonstrate the ability of the method to outperform structure-preserving linear subspace ROMs.
Angelegt am Thursday, 03.11.2022 20:38 von mohlb_01
Geändert am Monday, 30.01.2023 09:55 von mohlb_01
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Erika Roldan, MPI Leipzig: Topology and Geometry of Random Cubical Complexes (Oberseminar Mathematische Stochastik)
Wednesday, 01.02.2023 17:00 im Raum SRZ 216
In this talk, we explore the expected topology (measured via homology) and local geometry of two different models of random subcomplexes of the regular cubical grid: percolation clusters, and the Eden Cell Growth model. We will also compare the expected topology that these average structures exhibit with the topology of the extremal structures that it is possible to obtain in the entire set of these cubical complexes. You can look at some of these random structures here (https://skfb.ly/6VINC) and start making some guesses about their topological behavior.
Angelegt am Monday, 31.10.2022 09:36 von kollwit
Geändert am Thursday, 08.12.2022 09:34 von kollwit
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Titel: Simplicity of automorphism groups of homogeneous structures
Sprecher: Katrin Tent
und
Titel: Compact connected one-dimensional spaces
Sprecher: Aleksandra Kwiatkowska
Promotions- und Masterfeier des Fachbereiches Mathematik und Informatik
Monday, 06.02.2023 15:00 im Raum Aula des Schlosses
Wir werden auf dieser festlichen Veranstaltung mit anschließendem Umtrunk die Promovenden*innen und Masterabsolvenden*innen in eine erfolgreiche Zukunft verabschieden und würden uns sehr freuen, wenn Sie an dieser Feier teilnehmen würden.
Promotions- und Masterfeier des Fachbereiches Mathematik und Informatik am Montag, den 6.2.2023 um 15:00 Uhr in der Aula des Schlosses Schlossplatz 2
Der Dekan des Fachbereichs Mathematik und Informatik Prof. Dr. Xiaoyi Jiang, sowie der Fachbereich Mathematik und Informatik
Ellen Powell, Durham, UK: Brownian excursions, conformal loop ensembles and critical Liouville quantum gravity (Oberseminar Mathematische Stochastik)
Wednesday, 08.02.2023 17:00 im Raum SRZ 216
It was recently shown by Aidekon and Da Silva how to construct a growth fragmentation process from a planar Brownian excursion. I will explain how this same growth fragmentation process arises in another setting: when one decorates a certain ?critical Liouville quantum gravity random surface? with a conformal loop ensemble of parameter 4. This talk is based on joint work with Juhan Aru, Nina Holden and Xin Sun.
Angelegt am Thursday, 25.08.2022 12:29 von kollwit
Geändert am Wednesday, 18.01.2023 12:33 von kollwit
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