Upcoming Events
- Tuesday, 17.02.2026, 15:00 (WIAS-405-406)
- Seminar Modern Methods in Applied Stochastics and Nonparametric Statistics
Dr. Stefanos Theodorakopoulos, TU Berlin:
MFG with rough common noise
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Abstract
Motivated by mean-field games (MFG) with common noise on the one hand and pathwise stochastic control theory on the other, we formulate here a linear-quadratic (LQ) MFG with rough common noise, along with a satisfactory well-posedness theory for the linear-quadratic case. A novel Volterra-type (or mild) formulation allows to keep technical (rough-stochastic) consideration to a minimum. We derive a characterization of the optimal state and optimal control through a rough forward-backward stochastic differential equation (rough FBSDE or RFBSDE), and provide an existence and uniqueness result under the usual assumptions. Fi- nally, our results are accompanied by the corresponding stability estimates, while also proving the continuity property of what we call the Lyons-Lions-Ito map for rough mean-field games. (Joint work with Peter K. Friz, Ioannis Gasteratos, Ulrich Horst.)
Further Informations
Dieser Vortrag findet auch via Zoom statt: https://wias-berlin-de.zoom-x.de/j/69982487566
Host
WIAS Berlin
- Thursday, 19.02.2026, 10:30 (WIAS-Library)
- Software and Data Seminar
Dr. Laura Prieto Saavedra, WIAS Berlin:
The computer servers available at WIAS
more ... Location
Weierstraß-Institut, Hausvogteiplatz 5-7, 10117 Berlin, R411
Further Informations
Seminar Software and Data
Host
WIAS Berlin
- Tuesday, 24.02.2026, 15:00 (WIAS-405-406)
- Seminar Modern Methods in Applied Stochastics and Nonparametric Statistics
Jakob Kellermann, WIAS-Berlin:
Signature kernel ridge regression
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Further Informations
Dieser Vortrag findet auch via Zoom statt: https://wias-berlin-de.zoom-x.de/j/69982487566
Host
WIAS Berlin
- Wednesday, 25.02.2026, 11:30 (WIAS-406)
- Seminar Interacting Random Systems
Marta Dai Pra, Humboldt Universität zu Berlin:
Multi-type logistic branching processes with selection: frequency process and genealogy for large carrying capacities
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, 4. Etage, Weierstraß-Hörsaal (Raum: 406)
Abstract
We present a model for growth in a multi-species population. We consider two types evolving as a logistic branching process with mutation, where one of the types has a selective advantage. We first study the frequency of the disadvantageous type and show that, once the population approaches the carrying capacity, its evolution converges to a Gillespie-Wright-Fisher diffusion process. We then study the dynamics backward in time: we fix a time horizon at which the population is at carrying capacity and we study the ancestral relations of a sample of individuals. We prove that, provided that the advantageous and disadvantageous branching measures are ordered, this ancestral line process converges to the moment dual of the limiting diffusion. This talk is based on joint work with Julian Kern.
Further Informations
Seminar Interactin Random Systems
Host
WIAS Berlin
- Friday, 27.02.2026, 15:00 (WIAS-ESH)
- Joint Research Seminar on Nonsmooth Variational Problems and Operator Equations / Mathematical Optimization
Prof. Kei Fong Lam, Hong Kong Baptist University, Hong Kong:
Structural optimization with convex non-differentiable anisotropy: Application to 3D printing
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Abstract
3D printing is an umbrella term for a set of technologies that manufacture highly intricate and complex designs that are not feasible with traditional die-casting or injection molding methods. But despite their popularization in recent years, several limitations prevent further integration of 3D printing into existing production lines. One recurring issue relates to overhangs, which are regions of the constructed object that when placed in a certain orientation extend outwards without any underlying support. Some of these overhangs can deform under their own weight and, if not supported from below, present a risk in damaging the printed object. Conventional wisdom from practitioners says that overhangs whose outer normal makes an angle greater than 135 degrees with the upwards vertical direction should be supported from below with scaffolding. These are then removed after a successful print, but increase the material and processing costs. Another remedy is to modify the design to be self-supporting as much as possible without compromising its intended functionality. In this talk we consider the latter within a structural topology optimization framework. Extending previous studies with a linear elasticity model, we realize an overhang angle constraint with the help of a convex anisotropic perimeter functional, and study the corresponding optimal control problem. Earlier studies with non-convex functionals lead to instabilities termed the "dripping effect", which can be suppressed under our proposed framework. Numerical examples are provided to demonstrate how we discourage designs that develop overhangs not respecting the angle constraint. It turns out that for our approach we have to work with non-differentiable functionals, and thus we turn to subdifferential calculus to derive the first order optimality conditions. If time permits we will touch on a related aspect of 4D printing that builds on these technologies to create designs capable of changing their shape and functionalities via external stimulus. This is a joint work with Harald Garcke (Regensburg), Robert Nurnberg (Trento) and Andrea Signori (Pavia).
Further Informations
Joint Research Seminar on Nonsmooth Variational Problems and Operator Equations
Host
WIAS Berlin
- March 2 – 4, 2026 (IHP)
- Workshop/Konferenz: Leibniz MMS Days 2026
more ... Location
Leibniz Institute for High Performance Microelectronics Frankfurt/Oder
Host
Leibniz Institute for High Performance Microelectronics Frankfurt/Oder
WIAS Berlin
- Wednesday, 11.03.2026, 11:30 (WIAS-406)
- Seminar Interacting Random Systems
Anh Duc Vu, WIAS Berlin:
tba
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, 4. Etage, Weierstraß-Hörsaal (Raum: 406)
Abstract
tba
Further Informations
Seminar Interactin Random Systems
Host
WIAS Berlin
- Wednesday, 11.03.2026, 14:15 (WIAS-ESH)
- Berliner Oberseminar „Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Prof. Dr. Hannes Meinlschmidt, Friedrich-Alexander Universität Erlangen-Nürnberg:
Quasilinear parabolic equations in the Bessel scale
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Abstract
In this talk, I will discuss and analyze scalar quasilinear parabolic equations posed on nonsmooth domains with generally irregular input data. The latter refers to merely measurable and bounded coefficients, mixed boundary conditions, possibly inhomogeneous Robin or Neumann boundary data, and also to nonlinear forcing functions which may act on the gradient of the solution. The driving force for the analysis will be maximal parabolic regularity of the differential operators in the scale of (duals of) Bessel potential spaces incorporating mixed boundary conditions, with the scale parameter depending on the smoothness of the solution within the quasilinear operator. These depend on permanence principles for the elliptic counterparts which are leveraged from bilinear interpolation. A careful analysis allows to close the loop for the quasilinear equation and thus obtain local-in-time solutions under minimal assumptions. I further mention some sufficient criteria for solutions to exist globally, and how these can be leveraged in the framework of optimal control problems to achieve a satisfying theory for nonsmooth problems with strong nonlinearities.
Further Informations
Oberseminar “Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Host
Humboldt-Universität zu Berlin
WIAS Berlin
- March 16 – 18, 2026 (WIAS-ESH)
- Workshop/Konferenz: Workshop Optimal Transport and Noise: OT Meets (S)PDEs
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Host
Technische Universität Berlin
WIAS Berlin
- Thursday, 23.04.2026, 10:00 (WIAS-ESH)
- Forschungsseminar Mathematische Modelle der Photonik
Lasse Ermoneit, WIAS Berlin:
Epitaxial profile optimization in Si/SiGe heterostructures: Engineering valley splitting for spin qubits
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Further Informations
Forschungsseminar Mathematische Modelle der Photonik
Host
WIAS Berlin
- June 1 – 5, 2026 (WIAS-ESH)
- Workshop/Konferenz: ESGI 194 - The Berlin Study Group with Industry
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Host
WIAS Berlin
- July 6 – 8, 2026 (WIAS-ESH)
- Workshop/Konferenz: Spreading Dynamics in Random Environment
more ... Location
Weierstraß-Institut, Anton-Wilhelm-Amo-Str. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Host
WIAS Berlin