Special Involutions and Bulky Parabolic Subgroups in Finite Coxeter Groups
نویسندگان
چکیده
In [3] Felder and Veselov considered the standard and twisted actions of a finite Coxeter group W on the cohomology H(MW ) of the complement of the complexified hyperplane arrangement MW of W . The twisted action is obtained by combining the standard action with complex conjugation; we refer the reader to [3] for precise statements. In a case by case argument, Felder and Veselov obtain a formula for all Coxeter groups W for the standard action H(MW ) ∼= ∑ σ∈XW (2 · 1〈σ〉 − %)
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