10 kwietnia 2024 Leonardo Ferrari (IMPAN) Title: Isometries of tessellated rational homology spheres Abstract: In this talk, we will describe a combinatorial technique to build geometric manifolds from right-angled polytopes, discuss some topological and geometric properties of these manifolds, and explain an algorithm for the computation of their homology groups. We'll then present a faster algorithm for the detection of rational homology spheres, and discuss topological obstructions to their isometries. We'll finally present a method for building hyperbolic rational homology 3-spheres with isometries of given order, and mention open problems. No previous knowledge of hyperbolic geometry will be required in this talk.