Extending the Coinvariant Theorems of Chevalley, Shephard--Todd, Mitchell and Springer
arXiv:0805.3694 · doi:10.1112/plms/pdq027
Abstract
We extend in several directions invariant theory results of Chevalley, Shephard and Todd, Mitchell and Springer. Their results compare the group algebra for a finite reflection group with its coinvariant algebra, and compare a group representation with its module of relative coinvariants. Our extensions apply to arbitrary finite groups in any characteristic.
The applications and Examples in section 4 have been extended