English

A note on dual modules and the transpose

Rings and Algebras 2019-06-07 v1 Representation Theory

Abstract

It is a classical result in matrix algebra that any square matrix over a field can be conjugated to its transpose by a symmetric matrix. For FF a non-Archimedean local field, Tupan used this to give an elementary proof that transpose inverse takes each irreducible smooth representation of GLn(F){\rm GL}_n(F) to its dual. We re-prove the matrix result and related observations using module-theoretic arguments. In addition, we write down a generalization that applies to central simple algebras with an involution of the first kind. We use this generalization to extend Tupan's method of argument to GLn(D){\rm GL}_n(D) for DD a quaternion division algebra over FF.

Keywords

Cite

@article{arxiv.1906.02345,
  title  = {A note on dual modules and the transpose},
  author = {Thomas Madsen and Alan Roche and C. Ryan Vinroot},
  journal= {arXiv preprint arXiv:1906.02345},
  year   = {2019}
}
R2 v1 2026-06-23T09:44:27.817Z