FB 6 Mathematik/Informatik

Institut für Mathematik

Navigation und Suche der Universität Osnabrück





Dr. Kristina Schubert (Universität Osnabrück)

Fluctuation Results for General Ising Models - Block Spin Ising Models and Random Interactions

Starting from the classical Curie-Weiss model in statistical mechanics, we will consider more general Ising models. On the one hand, we introduce a block structure, i.e. a model of spins in which the vertices are divided into a finite number of blocks and where pair interactions are given according to their blocks. The magnetization is then the vector of magnetizations within each block, and we are interested in its behaviour and in particular in its fluctuations.
On the other hand, we consider Ising models on Erdős-Rényi random graphs. Here, I will also present results on the fluctuations of the magnetization.

Oberseminar Angewandte Analysis

29.06.2021 um 14:15 Uhr Meetingroom

Prof. Dr. Christian Weiß (Hochschule Ruhr West)

Approximating Borel measures by Dirac measures




Oberseminar Stochastik

Oberseminar Algebra

Oberseminar Topologie

23.06.2021 um 14:15 Uhr

Ahina Nandy (Universität Osnabrück)

Stable ∞-categories

30.06.2021 um 14:15 Uhr, Meetingroom, Code: 694168

Fangzhou Jin (Tongji University, China)

Gersten complexes and real étale sheaves

We discuss a connection between coherent duality and the Verdier-type duality on real schemes via a Gersten-type complex. This is a joint work with H. Xie.

07.07.2021 um 14:15 Uhr

Daniel Uschogov (Universität Osnabrück)


Osnabrücker Maryam Mirzakhani Lecture

30.06.2021 um 16:15 Uhr

Karin Schnass (Universität Innsbruck)

Conditioning of random submatrices 

I will motivate why it is useful to look at random submatrices where each atom is not drawn with the same probability but some atoms are more likely. I will then provide conditions under which such submatrices are well-conditioned with high probability, sketch the proof and show the crux of the proof in more detail. Time permitting we will then discuss how these results can be used to decide what a good sensing matrix for compressed sensing is and how we can precondition an existing one.
Joint work with Simon Ruetz.

07.07.2021 um 16:15 Uhr

Hannah Markwig (Eberhard Karls Universität Tübingen)

Kurven zählen und tropische Geometrie

Der Vortrag führt tropische Geometrie als ein Werkzeug zum Studium der enumerativen Geometrie ein. Erzeugendenreihen wichtiger enumerativer Zahlen treten in der Spiegelsymmetrie auf. In einigen Fällen können sie mit Feynmanintegralen in Zusammenhang gebracht werden und weisen interessante Eigenschaften auf, wie ihre Quasimodularität. Auch arithmetische und reelle Zählungen und ihre Zusammenhänge zur tropischen Geometrie werden betrachtet.