Buongiorno, dopodomani mercoledi' 27 maggio avra' luogo in aula seminari, alle ore 16, un seminario di Roman Sauer (Karlsruhe Institute of Technology). Seguono titolo e abstract. Saluti, Roberto Title: Volume and homology growth Abstract: Consider a tower of finite coverings of a closed manifold. We usually assume that the fundamental group is residually finite and that the tower corresponds to a residual chain of the fundamental group. We then ask: How does the size of the k-th homology group grow as we go up in the tower? By size we mean the rank or the cardinality of the torsion subgroup. We connect the homology growth for aspherical Riemannian manifolds in the above sense to the volume of balls.