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arXiv · 1912.11132

The Steinberg quotient of a tilting character

Paul Sobaje
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Abstract

Let $G$ be a simple algebraic group over an algebraically closed field of prime characteristic. If $M$ is a finite dimensional $G$-module that is projective over the Frobenius kernel of $G$, then its character is divisible by the character of the Steinberg module. In this paper we study such quotients, showing that if $M$ is an indecomposable tilting module, then the multiplicities of the orbit sums appearing in its "Steinberg quotient" are well behaved.

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BibTeXRIS

Paul Sobaje. 2020-02-05. The Steinberg quotient of a tilting character. https://arxiv.org/abs/1912.11132

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