3 problems

Let $E$ be a real quadratic field and let $\Gamma\subset\operatorname{SL}_3(\mathbb{Z})$ be a finite-index subgroup. Let $H(\Gamma,E)$ be the Steinberg-generated subspace, and let…

Let $\Gamma$ be a congruence subgroup of $\operatorname{SL}_3(\mathbb{Z})$, let $E$ be a real quadratic field, and let $H(\Gamma,E)$ be the Hecke-stable subspace of…

Let $X$ be an arithmetic locally symmetric space, let $\widehat X$ be its reductive Borel-Serre compactification, and let $X^*$ be its Baily-Borel compactification. Let…