Frobenius–schur Indicators of Unipotent Characters and the Twisted Involution Module
نویسندگان
چکیده
Let W be a finite Weyl group and σ a non-trivial graph automorphism of W . We show a remarkable relation between the σ-twisted involution module for W and the Frobenius–Schur indicators of the unipotent characters of a corresponding twisted finite group of Lie type. This extends earlier results of Lusztig and Vogan for the untwisted case and then allows us to state a general result valid for any finite group of Lie type. Inspired by recent work of Marberg, we also formally define Frobenius–Schur indicators for “unipotent characters” of twisted dihedral groups.
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