arXiv math/98110511998-11-23math.RAmath.COmath.GRmath.GTmath.RT

Semiinvariants of Finite Reflection Groups

Anne V. Shepler

备注：: Paper presented at 1999 Joint Meetings in San Antonio, special session on Geometry in Dynamics. Typo corrected
发表信息：: J. Algebra 220, 314-326 (1999).

英文摘要：

Let G be a finite group of complex n by n unitary matrices generated by reflections acting on C^n. Let R be the ring of invariant polynomials, and χbe a multiplicative character of G. Let Ω^χbe the R-module of χ-invariant differential forms. We define a multiplication in Ω^χand show that under this multiplication Ω^χhas an exterior algebra structure. We also show how to extend the results to vector fields, and exhibit a relationship between χ-invariant forms and logarithmic forms.

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