Ghent Methusalem Colloquium

The Ghent Methusalem Colloquium is intended for a broad audience of PhD students, postdocs and professors at the Ghent Analysis & PDE Center and beyond. The series includes colloquia from visiting and invited guests.

Upcoming Colloquia

Prof.  Philippe Souplet
Université Sorbonne

Paris Nord, France

Topic: Singularities of solutions of the diffusive Hamilton-Jacobi equation

Time: 16 December 2021
Where: Ghent University

We consider the diffusive Hamilton-Jacobi equation u_t-\Delta u=|\nabla u|^p, with homogeneous Dirichlet conditions, which plays an important role in stochastic control theory, as well as in certain models of surface growth (KPZ). Despite its simplicity, it displays, in the surquadratic case p>2, a variety of interesting behaviors and we will discuss two classes of phenomena:
– Gradient blowup (GBU): boundary localisation of singularities, single point point blowup, blowup rates, space and space-time profiles, Liouville type theorems and applications;
– Continuation after GBU as a global viscosity solution: GBU with or without loss of boundary conditions (LBC), recovery of of boundary conditions (RBC) with or without regularisation, multiple time GBU and LBC
In particular, in one space dimension, we will present the, recently obtained, complete classification of GBU and RBC rates and profiles.
Based on a series of joint works with A. Attouchi, R. Filippucci, Y. Li, N. Mizoguchi, A. Porretta, P. Pucci, Q. Zhang.