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arXiv · 0801.0874

Cyclotomic Solomon Algebras

Andrew Mathas·Rosa C. Orellana
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Abstract

This paper introduces an analogue of the Solomon descent algebra for the complex reflection groups of type $G(r,1,n)$. As with the Solomon descent algebra, our algebra has a basis given by sums of `distinguished' coset representatives for certain `reflection subgroups'. We explicitly describe the structure constants with respect to this basis and show that they are polynomials in $r$. This allows us to define a deformation, or $q$-analogue, of these algebras which depends on a parameter $q$. We determine the irreducible representations of all of these algebras and give a basis for their radicals. Finally, we show that the direct sum of cyclotomic Solomon algebras is canonically isomorphic to a concatenation Hopf algebra.

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Andrew Mathas, Rosa C. Orellana. 2008-05-09. Cyclotomic Solomon Algebras. https://arxiv.org/abs/0801.0874

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