Duality, Central Characters, and Real-valued Characters of Finite Groups of Lie Type
نویسنده
چکیده
We prove that the duality operator preserves the Frobenius–Schur indicators of characters of connected reductive groups of Lie type with connected center. This allows us to extend a result of D. Prasad which relates the Frobenius–Schur indicator of a regular real-valued character to its central character. We apply these results to compute the Frobenius–Schur indicators of certain real-valued, irreducible, Frobenius-invariant Deligne–Lusztig characters, and the Frobenius–Schur indicators of real-valued regular and semisimple characters of finite unitary groups.
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