A module-theoretic approach

to Clifford theory for blocks

Author:
S. J. Witherspoon

Journal:
Proc. Amer. Math. Soc. **128** (2000), 661-670

MSC (1991):
Primary 20C20, 20C25

DOI:
https://doi.org/10.1090/S0002-9939-99-05224-7

Published electronically:
July 8, 1999

MathSciNet review:
1646212

Full-text PDF Free Access

Abstract | References | Similar Articles | Additional Information

Abstract: This work concerns a generalization of Clifford theory to blocks of group-graded algebras. A module-theoretic approach is taken to prove a one-to-one correspondence between the blocks of a fully group-graded algebra covering a given block of its identity component, and conjugacy classes of blocks of a twisted group algebra. In particular, this applies to blocks of a finite group covering blocks of a normal subgroup.

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Additional Information

**S. J. Witherspoon**

Affiliation:
Department of Mathematics, University of Toronto, Toronto, Ontario, Canada M5S 3G3

Address at time of publication:
Department of Mathematics, University of Wisconsin, Madison, Wisconsin 53706

Email:
sjw@math.toronto.edu, sjw@math.wisc.edu

DOI:
https://doi.org/10.1090/S0002-9939-99-05224-7

Received by editor(s):
April 20, 1998

Published electronically:
July 8, 1999

Additional Notes:
Research supported in part by NSERC grant # OGP0170281.

Communicated by:
Ronald M. Solomon

Article copyright:
© Copyright 1999
American Mathematical Society