Local and Nonlocal Free Boundary Problems

ended

A wide class of physical phenomena can be mathematically formalized as Free Boundary (FB) problems, usually described by a set of Partial Differential Equations (PDEs) that exhibit also some unknown interfaces (the FB). The main goal is to describe as precisely as possible both the solution to the PDEs and the properties of the FB, an issue of significant theoretical complexity. In this project the Experienced Researcher (ER) presents different FB problems, depending on their nature: local/nonlocal and elliptic/parabolic. The first part is devoted to elliptic problems, with two objectives: the first one is to prove some quantitative regularity estimates for solutions to a class of elliptic semilinear equations related to Bernoulli one-phase type problems (local/nonlocal setting), while the second is to investigate the regularity/structure of the FB in a general nonlocal obstacle problem. Also the second part has two objectives (parabolic framework). The ER intends to study some nonlocal parabolic Bernoulli one-phase type problems. In this framework, the whole theory must be developed: the ER plans to study the existence of suitable weak solutions as well as their optimal regularity and the regularity/structure of the FB. The project contains innovative aspects, new techniques, and possesses a large number of applications to Physics, Engineering and Natural Sciences. The expected results are of great quality and will have significative impact in the PDEs community.