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arXiv · 2611.01803

RaFH and CRaFH superalgebras: Frobenius forms, representation theory and respectability

Abstract

We introduce \emph{RaFH superalgebras}, which are Rees affine Frobenius Hecke superalgebras. These algebras are defined by generators and relations, using \emph{Frobenius-tensor superalgebras} to axiomatise tensor powers of Frobenius superalgebras together with their copairing elements. The RaFH superalgebras include, as special cases, the affine and degenerate affine Hecke algebras of type $A$, the affine Sergeev superalgebras, the affine wreath product algebras and quantum affine wreath algebras, as well as the recently introduced quantum wreath product algebras in the special case of the superflip braiding. We study the RaFH superalgebras from both structural and representation theoretic points of view. We prove a basis theorem for the RaFH superalgebras, construct universal Jucys--Murphy elements, and classify their simple modules over an algebraically closed field via atomic superalgebras, which are smaller RaFH superalgebras of Hecke, Clifford or wreath type. We then study \emph{CRaFH superalgebras}, which are the cyclotomic quotients of the RaFH superalgebras. We construct bases for these superalgebras, and compute the Gram determinants of natural trace forms, and use these to determine when these superalgebras are symmetric or Frobenius. To study the representation theory of the CRaFH superalgebras, we introduce the \emph{respectable algebras}, which is a vast generalisation of cellular algebras, standardly based algebras and finite dimensional affine cellular algebras, and give many examples illustrating their variety and ubiquity. We then show that CRaFH superalgebras are respectable algebras with weight poset given by multipartitions that are coloured by the representations of the underlying Frobenius algebra. This result can be viewed as a far-reaching generalisation of Murphy's bases into the setting of CRaFH algebras.

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BibTeXRIS

Andrew Mathas, Catharina Stroppel. 2026-11-01. RaFH and CRaFH superalgebras: Frobenius forms, representation theory and respectability. https://arxiv.org/abs/2611.01803

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