Università di Milano-Bicocca *AVVISO DI SEMINARIO* Il prof. Wolfgang Woess (TU Graz, Austria), mercoledì 27 settembre, alle ore 14:30, nella stanza 3014 del Dipartimento di Matematica e Applicazioni (terzo piano U5), terrà un seminario dal titolo *Boundary behaviour of branching Markov chains* *Abstract: * We study multitype branching Markov chains on denumerable state(= type) spaces in discrete time. It is supposed that the offspring distributions satisfy a uniform "L log L" moment condition with state-independent expected offspring number, and that the associated "base" Markov chain on the state space is transient and irreducible. Given the population at time n at the different states, we normalize it by dividing by its total number. The resulting empirical distribution is a random probability measure on the state space. Assuming that the latter is equipped with a "geometric" compactification with a boundary at infinity, a main focus is on the question whether the sequence of empirical distributions converges a.s. weakly to a random probability distribution on the boundary. This is joint work with Vadim A. Kaimanovich (Ottawa), to appear in Ann. Inst Poincare' Prob. Stat. There is related, parallel work by Candellero and Hutchcroft. Tutti gli interessati sono invitati a partecipare.