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arXiv · 0805.1235

Schur-Weyl duality over finite fields

David Benson·Stephen Doty
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Abstract

We prove a version of Schur--Weyl duality over finite fields. We prove that for any field $k$, if $k$ has at least $r+1$ elements, then Schur--Weyl duality holds for the $r$th tensor power of a finite dimensional vector space $V$. Moreover, if the dimension of $V$ is at least $r+1$, the natural map $k\Sym_r \to End\_{GL(V)}(V^{\otimes r})$ is an isomorphism. This isomorphism may fail if $\dim_k V$ is not strictly larger than $r$.

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David Benson, Stephen Doty. 2009-06-30. Schur-Weyl duality over finite fields. https://arxiv.org/abs/0805.1235

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