2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/73770We apply spectral analysis of quotients of the Bruhat-Tits buildings of type $\tilde{A}_{d-1}$ to construct isospectral non-isomorphic Cayley graphs of the finite simple groups $\operatorname{PSL}_d({\mathbb F}_q)$ for every $d \geq 5$ ($d \neq 6$) and prime power $q > 2$.14 pagesCombinatoricsRepresentation Theory20F65, 11F72text