Sur Les Problèmes de Sortie Discrets Inhomogènes.

Let (X(t))t. 0 be a family of inhomogeneous Markov processes on a finite set M, whose jump intensities at the time s . 0 are given by exp(-.(t)s V(x, y))q(x, y) for all x . y . M, where the evolutions of the inverse of the temperature $\mathbb{R}_+ \ni s \mapsto \beta^{(t)}_s \in \mathbb{R}_+$ take in some ways greater and greater values with t. We study by using semigroup techniques the asymptotic behavior of the couple consisting of the renormalized exit time and exit position from sets which are a little more general than the cycles associated with the cost function V. We obtain a general criterion for weak convergence, for which we describe explicitly the limit law. Then we are interested in the particular case of evolution families satisfying . t, s . 0, .(t)s = .(0)t+s, for which we show there are only three kinds of limit laws for the renormalized exit time (this is relevant for the limit theorems satisfied by renormalized occupation times of generalized simulated annealing algorithms, but this point will not be developed here).