Abstract
A framework is given for defining and comparing factorizability
theories (as used,
for example, to relate modules over the group rings of finite groups).
The
strict theory
of Fröhlich [4] and the Hecke theory of
[7] as well as several other related theories are
shown to be equivalent. Of particular interest among the several equivalent
theories
examined is that of normaliser factorizability. This is perhaps the most
user friendly
theory and follows most closely the framework of the classical theory.
Among other
tools, the theory of permutation projectives and their species is used.
Publisher
Cambridge University Press (CUP)