Seminar on Banach and Metric Space Geometry

Date: April 21, 2017

Time: 3:00PM - 4:00PM

Location: BLOC 220

Speaker: Florence Lancien, Université de Franche-Comté

Title: Discrete analyticity for vector valued convolutions

Abstract: In 1986 G. Pisier showed that some convolution semigroups of operators are analytic bounded on Lp(X) for 1<p<∞ iff X is a K-convex Banach space. The analogue of analyticity for discrete semigroups is the notion of Ritt operators: T∈B(X) s.t. supn‖Tn(I-T)‖<∞. We show that Pisier's theorem adapts to this situation and explain how this is related to the question of subordination for discrete semigroups.This is joint work with C. Le Merdy