English

The Schur functor on tensor powers

Representation Theory 2011-02-28 v2

Abstract

Let MM be a left module for the Schur algebra S(n,r)S(n,r), and let sZ+s \in \mathbb{Z}^+. Then MsM^{\otimes s} is a (S(n,rs),FSs)(S(n,rs), F\mathfrak{S}_s)-bimodule, where the symmetric group Ss\mathfrak{S}_s on ss letters acts on the right by place permutations. We show that the Schur functor frsf_{rs} sends MsM^{\otimes s} to the (FSrs,FSs)(F\mathfrak{S}_{rs},F\mathfrak{S}_s)-bimodule FSrsF(SrSs)((frM)sFSs)F\mathfrak{S}_{rs} \otimes_{F(\mathfrak{S}_r \wr \mathfrak{S}_s)} ((f_rM)^{\otimes s} \otimes F\mathfrak{S}_s). As a corollary, we obtain the effect of the Schur functor on the Lie power Ls(M)L^s(M), symmetric power Ss(M)S^s(M) and exterior power s(M)\bigwedge^s(M) of MM.

Keywords

Cite

@article{arxiv.1102.4157,
  title  = {The Schur functor on tensor powers},
  author = {Kay Jin Lim and Kai Meng Tan},
  journal= {arXiv preprint arXiv:1102.4157},
  year   = {2011}
}

Comments

6 pages

R2 v1 2026-06-21T17:29:10.054Z