Seminario del Departamento de Ecuaciones Diferenciales y Análisis Numérico
Fecha : 14 de julio de 2014
Hora : 10:30
Lugar : Seminario del Departamento (Fac. de Matemáticas, 3a. planta, módulo 34)
Silvia Sastre Gómez
(Universidad Complutense de Madrid)
Nonlocal diffusion problem
Resumen
In this work we study the existence, uniqueness, comparison
properties and asymptotic behaviour of the solutions of some nonlocal diffusion
problems. All the problems in this work are set in metric measure spaces. These
spaces include very different type of spaces, for example, open subsets in
R^N, graphs, manifolds, multistructures or some fractal sets. First of all we study
the solutions of the linear nonlocal diffusion problem. In particular we describe
the asymptotic behaviour using spectral methods. After that we will study the
nonlinear nonlocal diffusion problem with a local reaction. In particular, we
prove weak and strong maximum principles and the existence of two extremal
equilibria, which attract the asymptotic dynamics of the solutions. We also
show how the lack of smoothing prevent us from proving the existence of a
global attractor. After that, we consider a nonlinear term that is a nonlinear
function of the average of the solution in a ball. In this case we prove that there
are strong restrictions for the weak and strong maximum principles to hold.
When these hold, we prove the existence of a global attractor.