Séminaires : Séminaire d'Analyse Fonctionnelle

Equipe(s) : af,
Responsables :E. Abakoumov - A.Eskenazis - D. Cordero-Erausquin - M. Fathi - O. Guédon - B. Maurey
Email des responsables :
Salle : salle 13 - couloir 15-16 - 4ème étage
Adresse :Campus Pierre et Marie Curie
Le Jeudi à 10h30 -  IMJ-PRG - 4 place Jussieu - 75005 PARIS

Orateur(s) Yuri Tomilov - Institute of Mathematics, Polish Academy of Sciences,
Titre On functional calculi, subordination and related matters
Horaire10:30 à 12:00
Roughly, given a semigroup of probability measures $ \mu=(\mu_t)_t \ge 0 $ and a semigroup of bounded operators $T=(T_t)_t \ge 0$ on a Banach space $X$, subordination provides a natural recipe to associate to them a new operator semigroup $T^\mu=(T^\mu_t)_t \ge 0$
on $X$ called a subordinated semigroup. Being an established subject of functional analysis, subordinated semigroups are of importance in e.g. probability and ergodic theories.

We will present solutions of several long-standing problems pertaining to the subordination of operator semigroups. The corresponding discrete analogues will also be discussed. Our arguments are based on the interplay between several functional calculi and certain function-theoretical estimates.

If time permits, we will explain how a telegram from Besicovitch to Littlewood enters the picture and produces an answer to a question of Erdös et al. originating from the discrete considerations.
Sallesalle 13 - couloir 15-16 - 4ème étage
AdresseCampus Pierre et Marie Curie