Title : Group actions and group extensions

Author : Erg{\" u}n Yal{\c c}{\i}n
         Indiana University, Department of Mathematics                  


Preprint, 1998

Abstract:

In this paper we study finite group extensions represented by special
cohomology classes. As an application we obtain some restrictions on
finite groups which can act freely on a product of spheres
or on a product of real projective spaces. In particular, we
prove that if $(Z/p)^r$ acts freely on $(S^1)^k$, then $r \leq k$.