Higher Kazhdan property and unitary cohomology of arithmetic groups

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Bader, Uri, Sauer, Roman
Formato: Preprint
Publicado: 2023
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866912882138021888
author Bader, Uri
Sauer, Roman
author_facet Bader, Uri
Sauer, Roman
contents Notions of higher Kazhdan property can be defined in terms of vanishing of unitary group cohomology in higher degrees. Garland's theorem for simple groups over non-archimedean fields provides the first examples of a higher Kazhdan property. We prove a version of Garland's theorem for simple Lie groups and their lattices. We generalize theorems of Borel and Borel-Yang about the invariance of the cohomology of lattices in semisimple Lie groups and adelic groups by improving the stability range and allowing for arbitrary unitary representations as coefficients. A novelty of our approach is the use of methods from geometric group theory and -- in the case of rank 1 -- from Clozel's work on the spectral gap property.
format Preprint
id arxiv_https___arxiv_org_abs_2308_06517
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Higher Kazhdan property and unitary cohomology of arithmetic groups
Bader, Uri
Sauer, Roman
Representation Theory
Algebraic Topology
Group Theory
22E41 (Primary), 22E46, 20G10 (Secondary)
Notions of higher Kazhdan property can be defined in terms of vanishing of unitary group cohomology in higher degrees. Garland's theorem for simple groups over non-archimedean fields provides the first examples of a higher Kazhdan property. We prove a version of Garland's theorem for simple Lie groups and their lattices. We generalize theorems of Borel and Borel-Yang about the invariance of the cohomology of lattices in semisimple Lie groups and adelic groups by improving the stability range and allowing for arbitrary unitary representations as coefficients. A novelty of our approach is the use of methods from geometric group theory and -- in the case of rank 1 -- from Clozel's work on the spectral gap property.
title Higher Kazhdan property and unitary cohomology of arithmetic groups
topic Representation Theory
Algebraic Topology
Group Theory
22E41 (Primary), 22E46, 20G10 (Secondary)
url https://arxiv.org/abs/2308.06517