Magnetic skyrmions
Thursday, 2.5.24, 15:00-16:00, Hörsaal II, Albertstr. 23b
Stress-mediated growth determines division site morphology of E. Coli
Tuesday, 7.5.24, 14:15-15:15, Raum 226, Hermann-Herder-Str. 10
Bacteria are enveloped by a rigid cell wall and replicate by cell division. During the division, the cell wall needs to be drastically reshaped. It is hypothesized that the remodeling process is stress-mediated and driven by the constrictive force of a protein assembly, the Z-ring. We found that a simple large-strain morpho-elastic model can reproduce the experimentally observed shape of the division site during the constriction and septation phases of E. Coli. Our model encapsulates the multiple enzyme-dependent wall restructuring processes into a single modulus. Depending on this parameter, different experimentally known morphologies can be recovered, corresponding either to mutated or wild type cells. In addition, a plausible range\nfor the cell stiffness and turgor pressure was determined by comparing numerical simulations with experimental data on cell lysis and reported cell sacculus deformation experiments.
Modellieren im Mathematikunterricht
Tuesday, 7.5.24, 18:00-19:00, Hörsaal II, Albertstr. 23b
Mathematisches Modellieren ist eine wichtige prozessbezogene Kompetenz, die in Bildungsstandards und Curricula in Deutschland, den USA und vielen anderen Ländern ausgewiesen ist. Im Vortrag werden der Stand der Forschung zu den Teilkompetenzen des Modellierens (unter anderem Verstehen, Mathematisieren und Validieren) vorgestellt und Lernumgebungen präsentiert, die sich förderlich auf die kognitive und motivationale Entwicklung von Schülerinnen und Schülern auswirken.
Informationsveranstaltung zum neuen Studiengang "M.Sc. Mathematics in Data and Technology"
Thursday, 16.5.24, 14:15-15:15, Hörsaal II, Albertstr. 23b
Physical Control of Soft Robots
Monday, 27.5.24, 14:15-15:15, Raum 226, Hermann-Herder-Str. 10
In this lecture I show that when multiple nonlinear soft actuators are interconnected they can also embody the control function, by leveraging the local negative stiffness of the actuators to drive their motion out of phase. This allows soft robots to move in pre-programmed sequence using only a single input.
Quantization of momentum maps and adapted formality morphisms
Monday, 27.5.24, 16:00-17:00, Raum 125, Ernst-Zermelo-Str. 1
If a Lie group acts on a Poisson manifold by Hamiltonian symmetries there is a well-understood way to get rid of unnecessary degrees of freedom and pass to a Poisson manifold of a lower dimension. This procedure is known as Poisson-Hamiltonian reduction. There is a similar construction for invariant star products admitting a quantum momentum map, which leads to a deformation quantization of the Poisson-Hamiltonian reduction of the classical limit. \n\nThe existence of quantum momentum maps is only known in very few cases, like linear Poisson structures and symplectic manifolds. The aim of this talk is to fill this gap and show that there is a universal way to find quantized momentum maps using so-called adapted formality morphisms which exist, if one considers nice enough Lie group actions. This is a joint work with Chiara Esposito, Ryszard Nest and Boris Tsygan.
Stationarity in beautiful pairs
Tuesday, 28.5.24, 14:30-15:30, Raum 404, Ernst-Zermelo-Str. 1
A type in a stable theory \(T\) is stationary if it has a unique non-forking extension. By adding imaginary elements to a model of \(T\), types over algebraically closed sets in the expanded structure become stationary. If \(T\) does not eliminate imaginaries, the question arises whether types over algebraically closed subsets in the original model (real subsets) are also stationary.\n\nAfter reviewing all the above notions, we will discuss this problem for the theory \(T_P\) of beautiful pairs of models of a stable theory \(T\) introduced by Poizat. By a result of Pillay and Vassiliev, this theory does not have (geometric) elimination of imaginaries if an infinite group is definable in \(T\). We will prove that types over real algebraically closed sets in \(T_P\) are stationary.
Periods via Motives and Species
Friday, 31.5.24, 10:30-11:30, Raum 404, Ernst-Zermelo-Str. 1
We explain how the structure theory of finite dimensional algebras can be used to deduce dimension formulas for period spaces of motives. They are sharp and unconditional in the case of 1-motives, i.e., periods of curves. (Joint work with Martin Kalck, Graz)