Upcoming Events
- Thursday, 10.04.2025, 10:00 (WIAS-405-406)
- Software and Data Seminar
Dr. Jan Philipp Thiele, WIAS Berlin:
Automated testing using GitLab CI/CD
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Further Informations
Software and Data Seminar
Host
WIAS Berlin
- Wednesday, 16.04.2025, 14:15 (WIAS-405-406)
- Berliner Oberseminar „Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Michael Tsopanopoulos, Humboldt-Universität zu Berlin:
Higher regularity for elliptic systems with mixed boundary conditions
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Host
Humboldt-Universität zu Berlin
WIAS Berlin
- Wednesday, 23.04.2025, 11:30 (WIAS-405-406)
- Seminar Interacting Random Systems
Mino Nicola Kraft, Technische Universität Darmstadt:
From quantum mechanics to stochastic processes
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Abstract
In this talk, we aim to use minimal assumptions to arrive at the relevance of stochastic processes to describe nature on a particle-scale. That is, we start with the foundation of a physical theory and introduce assumptions that are shared by classical and quantum mechanical theory. Then, pointing out the single difference between both theories from the theoretical point of view, I present how we arrive at the setting of a quantum particle in space. Generalizing to multiple particles, this is the setting used to describe the Bose gas which will serve as my main illustration. At this point, we will only have seen the theory from the functional analysis point of view and the next step is rewriting one particular expression with the help of stochastic processes which is often referred to as 'Feynman--Kac formula'. Working out the relevance of rewritten expression for the theory we have derived so far, we have derived a complete picture starting at foundations of a physical theory and culminating on the relevance of stochastic processes to study this theory.
Further Informations
Seminar Interactin Random Systems
Host
WIAS Berlin
- Wednesday, 23.04.2025, 14:15 (WIAS-405-406)
- Berliner Oberseminar „Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Dr. Piotr Wozniak, Freie Universität Berlin:
On stochastic homogenisation of integral functionals and differential operators
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Abstract
In this talk we look into a stochastic homogenisation result for integral functionals which, in the deformation variable, depend on a linear differential operator of order one. Assuming stationarity of the random intergrands in conjunction with with the Hörmander ellipticity condition on the operator, we show existence of a homogenised random integral functional. With the aid of Akcloglu-Krengel's ergodicity theorem we further characterise the limiting integrand in terms of an asymptotic cell formula. This result extends the classical qualitative result of Dal Maso and Modica for the full gradient case.
Further Informations
Oberseminar “Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Host
Humboldt-Universität zu Berlin
WIAS Berlin
- Wednesday, 30.04.2025, 14:15 (WIAS-Library)
- Berliner Oberseminar „Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Dr. Rossella Giorgio, Technische Universität Wien, Österreich:
Nonlocal analysis of energies in micromagnetics
more ... Location
Weierstraß-Institut, Hausvogteiplatz 5-7, 10117 Berlin, R411
Abstract
In this talk we provide conditions in order to formally justify a nonlocal analysis of energies in Micromagnetics. Specifically, we first consider a nonlocalto-local approximation of exchange energy functionals, extending the wellknown Bourgain--Brezis--Mironescu formula to encompass the scenario where antisymmetric contributions are encoded. The key points are a pointwise convergence result and a Gamma-convergence argument. After the nonlocal approximation, we investigate the existence and qualitative properties of minimizers, focusing on the competition between a nonlocal symmetric exchange interaction, which penalizes spatial variations in magnetization, and a magnetostatic self-energy term that accounts for long-range dipolar interactions. For spherical domains, we generalize Brown's fundamental results by identifying critical radii such that uniform magnetizations are preferable for the small-body regime, while non-uniform magnetization configurations become dominant in the large-body regime. This is joint work with E. Davoli, G. Di Fratta and L. Lombardini.
Further Informations
Oberseminar “Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Host
Humboldt-Universität zu Berlin
WIAS Berlin
- Wednesday, 07.05.2025, 14:15 (WIAS-405-406)
- Berliner Oberseminar „Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Prof. Dr. Edriss Titi, University of Cambridge, UK and Texas A&M University, USA:
On a generalization of the Bardos--Tartar conjecture to nonlinear dissipative PDEs
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Abstract
In this talk I will show that every solution of a KdV-Burgers--Sivashinsky type equation blows up in the energy space, backward in time, provided the solution does not belong to the global attractor. This is a phenomenon contrast to the backward behavior of the 2D Navier--Stokes equations, subject to periodic boundary condition, studied by Constantin, Foias, Kukavica and Majda, but analogous to the backward behavior of the Kuramoto--Sivashinsky equation discovered by Kukavica and Malcok. I will also discuss the backward behavior of solutions to the damped driven nonlinear Schrödinger equation, the complex Ginzburg--Landau equation, and the hyperviscous Navier--Stokes equations. In addition, I will provide some physical interpretation of various backward behaviors of several perturbations of the KdV equation by studying explicit cnoidal wave solutions. Furthermore, I will discuss the connection between the backward behavior and the energy spectra of the solutions. The study of backward behavior of dissipative evolution equations is motivated by a conjecture of Bardos and Tartar which states that the solution operator of the two-dimensional Navier--Stokes equations maps the phase space into a dense subset in this space.
Further Informations
Oberseminar “Nichtlineare partielle Differentialgleichungen” (Langenbach-Seminar)
Host
Humboldt-Universität zu Berlin
WIAS Berlin
- Monday, 19.05.2025, 11:30 (WIAS-405-406)
- Seminar Interacting Random Systems
Peter Gracar, University of Leeds:
tba
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Further Informations
Seminar Interacting Random Systems
Host
WIAS Berlin
- Wednesday, 21.05.2025, 11:30 (WIAS-405-406)
- Seminar Interacting Random Systems
Adrian Röllin, National University of Singapore:
Centered Subgraph Counts in Dense Random Graphs
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Abstract
Complex networks appear in many fields, from social media to biology, and understanding their structure often boils down to studying how frequently small subgraphs (such as triangles or squares) appear. In this talk, I will introduce the idea of centered subgraph counts: a way of measuring subgraph occurrences that corrects for the dependence that we observe among regular subgraph counts. By focusing on these centered counts, we can describe and quantify the natural 'fluctuations' in dense random networks via tools first developed by Janson and Nowicki in the study of generalised U-statistics in the 90s. I will explain how these theoretical results lead to practical methods for assessing how well a given network fits a chosen statistical model--often referred to as a goodness-of-fit analysis.
Further Informations
Seminar Interactin Random Systems
Host
WIAS Berlin
- Wednesday, 04.06.2025, 11:30 (WIAS-405-406)
- Seminar Interacting Random Systems
Elena Pulvirenti, Delft University of Technology:
tba
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, 4. Etage, Raum: 405/406
Further Informations
Seminar Interacting Random Systems
Host
WIAS Berlin
- June 23 – 26, 2025 (Harnack-Haus)
- Workshop/Konferenz: 4th Annual Conference of SPP 2265 Random Geometric Systems 2025
more ... Location
Harnack-Haus -- Tagungsstätte der Max-Planck-Gesellschaft
Host
WIAS Berlin
- September 29 – October 1, 2025 (WIAS-ESH)
- Workshop/Konferenz: Mathematical Analysis of Fluid Flows by Variational Methods
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Host
Freie Universität Berlin
Universität Leipzig
WIAS Berlin
- October 15 – 17, 2025 (WIAS-ESH)
- Workshop/Konferenz: Recent Developments in Spatial Interacting Random Systems
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal
Host
WIAS Berlin