Research Interests
$\bullet$ Operator algebras associated with groups.
$\bullet$ Geometric and analytic group theory.
$\bullet$ Expander graphs.
Selected Publications of Tim de Laat
$\bullet$ Y. Arano, T. de Laat, and J. Wahl. Howe–moore type theorems for quantum groups and rigid $c^{\ast}$-tensor categories. Compositio Mathematica, 154(2):328–341, 2018.
$\bullet$ T. de Laat, M. Mimura, and M. de la Salle. On strong property ( T) and fixed point properties for Lie groups. Ann. Inst. Fourier (Grenoble), 66(5):1859–1893, 2016.
$\bullet$ U. Haagerup and T. de Laat. Simple Lie groups without the Approximation Property {II}. Trans. Amer. Math. Soc., 368(6):3777–3809, 2016.
$\bullet$ U. Haagerup, S. Knudby, and T. de Laat. A complete characterization of connected Lie groups with the Approximation Property. Ann. Sci. \'Ec. Norm. Supér. (4), 49(4):927–946, 2016.
$\bullet$ T. de Laat and M. de la Salle. Approximation properties for noncommutative $L^p$-spaces of high rank lattices and nonembeddability of expanders. J. Reine Angew. Math. (ahead of print), 2015+. {doi:10.1515/crelle-2015-0043}
$\bullet$ T. de Laat and M. de la Salle. Strong property ( T) for higher-rank simple Lie groups. Proc. Lond. Math. Soc. (3), 111(4):936–966, 2015.
$\bullet$ T. de Laat. On the Grothendieck theorem for jointly completely bounded bilinear forms. In Operator algebra and dynamics, volume 58 of Springer Proc. Math. Stat., pages 211–221. Springer, Heidelberg, 2013.
$\bullet$ T. de Laat. Approximation properties for noncommutative $L^p$-spaces associated with lattices in Lie groups. J. Funct. Anal., 264(10):2300–2322, 2013.
$\bullet$ U. Haagerup and T. de Laat. Simple Lie groups without the Approximation Property. Duke Math. J., 162(5):925–964, 2013.
$\bullet$ G. Heckman and T. de Laat. On the regularization of the Kepler problem. J. Symplectic Geom., 10(3):463–473, 2012.
Current Publications
$\bullet $ Tim de Laat and Mikael de la Salle. Actions of higher rank groups on uniformly convex Banach spaces. arXiv e-prints, March 2023. arXiv:2303.01405.
$\bullet $ Tim de Laat and Safoura Zadeh. Weak$_*$-continuity of invariant means on spaces of matrix coefficients. J. Math. Anal. Appl., 506(2):125669, February 2022. doi:10.1016/j.jmaa.2021.125669.
$\bullet $ Goulnara Arzhantseva, Dawid Kielak, Tim de Laat, and Damian Sawicki. Origami expanders. arXiv e-prints, December 2021. arXiv:2112.11864.
$\bullet $ Tim de Laat and Timo Siebenand. Exotic group $C^*$-algebras of simple Lie groups with real rank one. Ann. Inst. Fourier, 71(5):2117–2136, December 2021. doi:10.5802/aif.3441.
$\bullet $ Tim de Laat and Mikael de la Salle. Banach space actions and L2-spectral gap. Anal. PDE, 14(1):45–76, February 2021. doi:10.2140/apde.2021.14.45.
$\bullet $ Dennis Heinig, Tim de Laat, and Timo Siebenand. Group $C^*$-algebras of locally compact groups acting on trees. arXiv e-prints, November 2020. arXiv:2011.11265.
$\bullet $ Tim de Laat and Federico Vigolo. Superexpanders from group actions on compact manifolds. Geometriae Dedicata, 200(1):287–302, June 2019. doi:10.1007/s10711-018-0371-0.