Non-vanishing unitary cohomology of low-rank integral special linear groups

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Brück, Benjamin, Hughes, Sam, Kielak, Dawid, Mizerka, Piotr
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914362076168192
author Brück, Benjamin
Hughes, Sam
Kielak, Dawid
Mizerka, Piotr
author_facet Brück, Benjamin
Hughes, Sam
Kielak, Dawid
Mizerka, Piotr
contents We construct explicit finite-dimensional orthogonal representations $π_N$ of $\operatorname{SL}_{N}(\mathbb{Z})$ for $N \in \{3,4\}$ all of whose invariant vectors are trivial, and such that $H^{N - 1}(\operatorname{SL}_{N}(\mathbb{Z}),π_N)$ is non-trivial. This implies that for $N$ as above, the group $\operatorname{SL}_{N}(\mathbb{Z})$ does not have property $(T_{N-1})$ of Bader-Sauer and therefore is not $(N-1)$-Kazhdan in the sense of De Chiffre-Glebsky-Lubotzky-Thom, both being higher versions of Kazhdan's property $T$.
format Preprint
id arxiv_https___arxiv_org_abs_2410_22310
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Non-vanishing unitary cohomology of low-rank integral special linear groups
Brück, Benjamin
Hughes, Sam
Kielak, Dawid
Mizerka, Piotr
Group Theory
Algebraic Topology
11F75, 20J06, 55-08
We construct explicit finite-dimensional orthogonal representations $π_N$ of $\operatorname{SL}_{N}(\mathbb{Z})$ for $N \in \{3,4\}$ all of whose invariant vectors are trivial, and such that $H^{N - 1}(\operatorname{SL}_{N}(\mathbb{Z}),π_N)$ is non-trivial. This implies that for $N$ as above, the group $\operatorname{SL}_{N}(\mathbb{Z})$ does not have property $(T_{N-1})$ of Bader-Sauer and therefore is not $(N-1)$-Kazhdan in the sense of De Chiffre-Glebsky-Lubotzky-Thom, both being higher versions of Kazhdan's property $T$.
title Non-vanishing unitary cohomology of low-rank integral special linear groups
topic Group Theory
Algebraic Topology
11F75, 20J06, 55-08
url https://arxiv.org/abs/2410.22310