Im Rahmen des Mathematischen Forschungskolloquiums hält Hr. Dr. Rainer Klages (Queen Mary University of London) einen Vortrag zum Thema:"Transition to anomalous dynamics in simple random maps"  weiterlesen

18. Dezember 2023, 14:00 Uhr, Raum 222 (Ulmenstr. 69, Haus 3), 
Kolloquiumsleiter: Dr. Wolfram Just

Im Rahmen des Mathematischen Forschungskolloquiums hält Fr. PD Dr. Isabelle Schneider (FU Berlin) einen Vortrag zum Thema: "Symmetry groupoids of dynamical systems".

Symmetries described by group transformations help immensely in our task to qualitatively characterize solutions of dynamical systems - providing that they exist. In this talk based on my habilitation thesis, we significantly enlarge the class of dynamical systems which can be studied by symmetry methods, moving our focus from groups to groupoids as the underlying algebraic structure describing symmetry. Building on the groupoid framework, we fundamentally generalize the notion of equivariance and equivariant bifurcation theory. We will also outline first applications in modelling and control of dynamical systems.

Donnerstag, 14.12.2023, 14:00 Uhr, Raum 221 (Ulmenstr. 69, Haus 3)
Kolloquiumsleiter: Prof. Dr. Jens Starke

Im Rahmen des Mathematischen Institutskolloquiums hält Herr Prof. Joachim Wagner (Universität Rostock) einen Vortrag zum Thema:
"Berechnung von zweiten Virialkoeffizienten konvexer Körper im D-dimensionalen Vektorraum mittels der Brunn-Minkowski-Theorie". weiterlesen
Auch interessierte Studierende sind herzlich eingeladen.

Mittwoch, 06.12.2023, 15:00 Uhr, Ulmenstr. 69, Haus 3, HS 228
Kolloquiumsleiter: Prof. Dr. Achill Schürmann

Im Rahmen des Mathematischen Forschungskolloquiums hält Hr. Ing. Ph. D. Lukas Kotrla (Universität Pilsen, Tschechien) einen Vortrag zum Thema: "Nonuniqueness and multi\--bump solutions in parabolic problems with the $p$-Laplacian".

The validity of the weak and strong comparison principles for degenerate parabolic partial differential equations with the p-Laplace operator Delta_p is investigated for p > 2. This
problem is reduced to the comparison of the trivial solution (≡ 0, by hypothesis) with a nontrivial nonnegative solution u(x,t).

Mittwoch, 06.12.2023, 16:00 Uhr, HS 125 (Ulmenstr. 69, Haus 3)
Kolloquiumsleiter: Prof. Dr. Peter Takác, Ph. D.

Im Rahmen des Mathematischen Institutskolloquiums hält Herr Dr. Sebastian Fuchs (University of Salzburg, Austria) einen Vortrag zum Thema:
"A model-free and dependence-based variable selection method for multi-outcome data". weiterlesen
Auch interessierte Studierende sind herzlich eingeladen.

Mittwoch, 01.11.2023, 15:15 Uhr - ca. 17:00 Uhr, Ulmenstr. 69, Haus 3, HS 326/327  

Im Rahmen des Mathematischen Forschungskolloquiums hält Hr. Dr. Rainer Klages (Queen Mary University of London) einen Vortrag zum Thema:"Stochastic modelling of biological motion: sea turtles, bumblebees and crawling cells"  weiterlesen
Auch interessierte Studierende sind herzlich eingeladen.
25. Oktober 2023, 15:15 Uhr, HS 326/327 (Ulmenstr. 69, Haus 3), 
Kolloquiumsleiter: Dr. Wolfram Just

Im Rahmen des Mathematischen Institutskolloquiums hält Prof. Jon Star (Harvard - Graduate School of Education, Cambridge) einen Vortrag zum Thema: "Mathematical flexibility: A promising focus for research and practice".

"Mathematical flexibility is increasingly recognized as an important construct of interest for both researchers and practitioners in mathematics education. Flexibility can be characterized as a learner's willingness to change strategies based on the particular problem-solving conditions or goals. In this talk, I first provide an introduction to flexibility. I then explore different ways that flexibility has been assessed, highlighting successes and challenges in the various forms of assessment. I then present recent empirical research results on flexibility, and I conclude by suggesting some promising areas for future research on flexibility."

Auch interessierte Studierende sind herzlich eingeladen.

Freitag, 06.10.2023, 15:00 - 17:00 Uhr, Ulmenstr. 69, Haus 3, SR 228

28.07.2023, Ulmenstr. 69, Haus 3, HS 326/327

15:00 Uhr: Benno Rumpf (Southern Methodist University, Dallas, US)

Cold breathers: a statistical explanation for the localization of energy in nonlinear Klein-Gordon lattices

Localization of energy via the formation of discrete breathers is a common, but slightly counterintuitive event in the dynamics of nonlinear lattices. There is a simple statistical explanation for this phenomenon in lattices that conserve a second quantity in addition to the Hamiltonian; in the case of nonlinear Schrödinger systems this second quantity is the wave action. It turns out that the localization of energy is quite similar to the formation of droplets in saturated steam. Unfortunately, this explanation fails for lattices whose only conserved quantity is the Hamiltonian, e.g., nonlinear Klein-Gordon lattices. I will suggest a new explanation for this phenomenon.

26.07.2023, Ulmenstraße 69, Haus 3, HS 326/327

15:00 Uhr : Julia Slipantschuk (University of Warwick, Warwick, UK)

Transfer operators and applications

I will give a short introduction to the theory of transfer operators and explain how the spectral properties of these operators yield insight into the long-term behaviour of the underlying dynamical system. For sufficiently chaotic dynamical systems, the exponential mixing rates are obtained from the eigenvalues of the associated transfer operator.  In very few non-trivial cases it is possible to determine all the mixing rates explicitly. On the other hand, it is often possible to approximate these operators by finite rank operators, and show convergence of the eigenvalues obtained from the respective matrix representations to the actual eigenvalues of the operator.

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Ulmenstr. 69, Haus 3, HS 326/327

16:00 Uhr: Oscar F. Bandtlow (Queen Mary University of London, London, UK)

Spectral approximation of evolution operators using dynamical mode decomposition

A class of algorithms known as extended dynamic mode decomposition (EDMD) has been shown to be empirically effective at identifying intrinsic modes of a dynamical system from time-series data. The algorithm amounts to constructing an NxN matrix by observing a dynamical system through N observables at a sequence of M phase space points. While empirically successful, there are few rigorous results on the convergence this algorithm. Moreover, the relationship between M and N remains obscure.

In this talk I will focus on analytic expanding circle maps and show that spectral data of the EDMD matrices can be linked to spectral data (for example eigenvalues, also known as Ruelle resonances in this context) of the Perron-Frobenius operator or its dual, the Koopman operator, associated to the underlying map, provided both operators are considered on suitable function spaces. In particular, I will show that for equidistantly chosen phase space points, spectra of the EDMD matrices converge to the Ruelle resonances at exponential speed in N, provided that the number of data points M is chosen to be a constant multiple of N, where the constant depends on complex expansion properties of the underlying analytic circle map.

This is joint work with Wolfram Just and Julia Slipantschuk.

Im Rahmen des Mathematischen Institutskolloquiums hält Frau Dr. Alethea B. T. Barbaro (Associate Professor) einen Vortrag zum Thema: "A model for territorial development: from particles to continuum". Auch interessierte Studierende sind herzlich eingeladen.

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Der 'Tag der Mathematik 2023' und der Wettbewerb um den 'Pokal der Rektorin' werden am 24.06.2023 auf dem 'Campus Ulmenstraße 69' durchgeführt. 
(Lageplan)

Im Rahmen des Mathematischen Institutskolloquiums hält Frau Prof. Ursula Müller-Harknett (Universität Rostock) einen Vortrag zum Thema: "Estimating the error distribution in semiparametric models". Auch interessierte Studierende sind herzlich eingeladen.

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Im Rahmen des Mathematischen Institutskolloquiums hält Herr Léo Perrin (INRIA Paris Centre, France) einen Vortrag zum Thema: "How can we ensure that (symmetric) cryptographic primitives are trustworthy?". Auch interessierte Studierende sind herzlich eingeladen.
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Der Hochschulinformationstag (HIT) ist ein jährlich stattfindender Informationstag für an einem Studium interessierte Schülerinnen und Schüler.
Einen Überblick über alle Veranstaltungen findet Ihr hier.

Veranstaltungen des Instituts für Mathematik - in Bearbeitung -

Am 04.05.2023 findet die diesjährige 'Lange Nacht der Wissenschaften' ab 16 Uhr schwerpunktmäßig auf dem Campus Südstadt statt.
weiterlesen

Im Rahmen des Mathematischen Institutskolloquiums hält Herr Prof. Henning Stichtenoth (Sabanci University, Istanbul - Turkey) einen Vortrag zum Thema: "Rational Points on curves over finite fields". Auch interessierte Studierende sind herzlich eingeladen.

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Im Rahmen des Mathematischen Institutskolloquiums hält Herr Prof. Gary Froyland (School of Mathematics and Statistics, University of New South Wales) einen Vortrag zum Thema: "Transfer operator analysis of the ocean and climate". Auch interessierte Studierende sind herzlich eingeladen.

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Im Rahmen des Mathematischen Institutskolloquiums hält Herr Dr. Tappe (Institut für Mathematik, Universität Rostock) einen Vortrag zum Thema:
"Stochastic partial differential equations and invariant manifolds in embedded Hilbert spaces". 
Das Kolloquium findet diesmal ausschließlich als Zoom-Meeting online statt.

Auch interessierte Studierende sind herzlich eingeladen. Weitere Informationen