As part of the research seminars of the Institute of Applied Analysis, Marie Borrmann (University of Bonn) will give a lecture on 2.2.26 on the following topic

Topic: "A gradient flow that is none: Heat flow with Wentzell boundary conditions".

Date: 02.02.2026

Time: 4:15 pm

Room: Helmholtzstrasse 18, Room E.60

Abstract:

We establish a representation of the heat flow with Wentzell boundary conditions on smooth domains as gradient descent dynamics for the entropy in a suitably extended Otto manifold of probability measures with additional boundary parts. Yet we show that for weak boundary diffusion the associated Fokker-Planck dynamics cannot be recovered from any entropy-driven metric JKO-Wasserstein scheme, at least if the underlying point metric satisfies certain natural regularity assumptions.

The talk is based on joint work with Léonard Monsaingeon, Michiel Renger and Max von Renesse.