Random lifts and cutoff phenomenon

schedule le lundi 14 octobre 2019 de 17h00 à 18h00

Organisé par : F. Bechtold, W. Da Silva , A. Fermanian, S. Has, Y. Yu

Intervenant : Guillaume Conchon-Kerjan (LPSM)
Lieu : P7 Sophie Germain Room 1016

Sujet : Random lifts and cutoff phenomenon

Résumé :

A random walk on a Markov chain undergoes a cutoff when the empirical distribution of its position on the chain converges 'suddenly' to the invariant measure. This phenomenon was initially highlighted when trying to determine the crucial number of moves to mix a deck of cards. In recent years, much progress was made outside casinos as cutoff was exhibited on d-regular graphs with n vertices (for fixed d>2 and n going to infinity). In this talk, we will focus on an other regular sparse model of graph, namely random lifts of a fixed base graph.