Tim de Laat

activity

20162023

collaborators

8 papers

math.OA2023

Dynamical propagation and Roe algebras of warped spaces

Tim de Laat, Federico Vigolo, Jeroen Winkel

Given a non-singular action $Γ ↷ (X, μ)$ , we define the $*$ -algebra $C_{fp} [Γ ↷ X]$ of operators of finite dynamical propagation associated w…

math.GR2023

Actions of higher rank groups on uniformly convex Banach spaces

Tim de Laat, Mikael de la Salle

We prove that all isometric actions of higher rank simple Lie groups and their lattices on arbitrary uniformly convex Banach spaces have a fixed point. This vastly generalises a re…

math.FA2021

Weak*-continuity of invariant means on spaces of matrix coefficients

Tim de Laat, Safoura Zadeh

With every locally compact group $G$ , one can associate several interesting bi-invariant subspaces $X (G)$ of the weakly almost periodic functions $WAP (G)$ on $G$ , each of…

math.OA2019

Exotic group $C^{*}$ -algebras of simple Lie groups with real rank one

Tim de Laat, Timo Siebenand

Exotic group $C^{*}$ -algebras are $C^{*}$ -algebras that lie between the universal and the reduced group $C^{*}$ -algebra of a locally compact group. We consider simple Lie groups $G$ with…

math.OA2017

The Fourier algebra of a rigid $C^{*}$ -tensor category

Yuki Arano, Tim de Laat, Jonas Wahl

Completely positive and completely bounded mutlipliers on rigid $C^{*}$ -tensor categories were introduced by Popa and Vaes. Using these notions, we define and study the Fourier-…

math.MG2017

Superexpanders from group actions on compact manifolds

Tim de Laat, Federico Vigolo

It is known that the expanders arising as increasing sequences of level sets of warped cones, as introduced by the second-named author, do not coarsely embed into a Banach space as…