On a theorem of Feit and Tits

Kleidman, Peter B.; Liebeck, Martin W.

doi:10.1090/S0002-9939-1989-0961412-6

On a theorem of Feit and Tits
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by Peter B. Kleidman and Martin W. Liebeck

Proc. Amer. Math. Soc. 107 (1989), 315-322

DOI: https://doi.org/10.1090/S0002-9939-1989-0961412-6

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Abstract:

Feit and Tits [3] lay the groundwork for determining the smallest degree of a projective representation of a finite extension of a finite simple group $G$. Provided $G$ is not of Lie type in characteristic 2, they determine precisely when this degree is smaller than the degree of a projective representation of $G$ itself. We complete this project by extending their results to the groups of Lie type in characteristic 2.

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