Rigid modules and homological dimensions

We make use of the concepts of Tor-rigid and rigid-test modules, among others, to investigate the interplay between cohomology vanishing and the finiteness of several homological dimensions such as projective, injective and Gorenstein injective dimensions. Besides criteria for the freeness of modules, the applications include new characterizations of Gorenstein and regular local rings, which are also of interest in the realm of algebraic geometry.
Comment: Several interesting suggestions have arrived concerning the manuscript, so it will be rewritten and largerly improved in a forthcoming version (possibly with a different title)