Institutos Universitarios

Non-linear non-local PDEs, stochastic particles, and particle systems

Brief description

Linear and non-linear PDEs of local type were key in many settings during the 20th century. For example, the heat equation, which involves a Laplacian. This equation is linked to Brownian Motion, a continuous stochastic process. In the past decades, this idea has evolved in two directions. Brownian-like models lead to spatial exponential decay of the density, which does not capture many practical problems (e.g., in finance), and more general model with power-type decay could be introduced, for example through Lévy flights. These are related to some non-local operators like the fractional Laplacian. We will study theoretical and numerical questions related to this operator: well-posedness, homogenisation, rearrangement, approximation schemes, … Another interesting topic is Stochastic Differential Games, such as tug-of-war games. Some choices lead to the p-Laplace equation, and one of our aims is to study examples leading to non-local linear and non-linear problem. We will also study a different type of non-local problem. Considering more than one particle interacting a distance (e.g., gravitational forces, chemical interaction, …) leads to non-local PDEs. A particularly interesting set of these problems is the family known as Aggregation-Diffusion problems, in which some members of the team have been working over the last years.

 

Researchers

  • David Gómez Castro. PhD Teaching Assistant (Ayudante Doctor), School of Mathematical Sciences (Facultad de CC Matemáticas), UCM (PI)
  • Ángel René Arroyo García. Assistant Professor (Profesor Ayudante Doctor), School of Mathematical Sciences (Facultad de CC Matemáticas), UCM
  • Jesús Ildefonso Díaz Díaz. Professor Emeritus (Catedrático Emérito), Member of the Royal Academy of Sciences (Miembro de la RAC)
  • Juan Carlos Felipe Navarro. Assistant Professor (Profesor Ayudante Doctor), School of Mathematical Sciences (Facultad de CC Matemáticas), UCM

 

External Collaborators

  • Gregorio Díaz Díaz (Retired Prof of Applied Mathematics, UCM)
  • Jesús Hernández (Retired Prof of Mathematics, UCM)

 

Publications

  • J. Ildefonso Díaz, A. V. Podolskiy, T. A. Shaposhnikova. Unexpected regionally negative solutions of the homogenization of Poisson equation with dynamic unilateral boundary conditions: critical symmetric particles. Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas 118, 9. 2024. https://doi.org/10.1007/s13398-023-01503-w
  • P. Bégout and J. I. Díaz, Finite time extinction for critically damped Schrodinger equation with a sublinear nonlinearity. Advances in Differential Equations, Volume 28, Numbers 3-4 (2023), 311-340. https://hal.science/hal-03805319v1

 


News