Title: Existence of quasi-stationary distributions.
Quasi-stationary distribution is a concept related to
stochastic processes with absorbing states. It formalizes the idea of
"regular behavior" in, for example, spreading of an infection among a
finite population.
I will talk about the problem of its existence in non-finite spaces.
The approach we are taking involves an interacting particle system
(Fleming-Viot) and a study of its empirical profile.
In this way we are able to establish a sufficient condition for
existence of a quasi-stationary distribution and moreover, to give an
explicit construction.
