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arXiv · 2306.14002

A counterexample to a conjecture on Cartan determinants of monoid algebras

Florian Eisele
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Abstract

We show that there are finite monoids $M$ such that the Cartan matrix of the monoid algebra $\mathbb C M$ is non-singular, whilst the Cartan matrix of $kM$ is singular for some field $k$ of positive characteristic, disproving a recent conjecture of Steinberg.

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BibTeXRIS

Florian Eisele. 2023-06-24. A counterexample to a conjecture on Cartan determinants of monoid algebras. https://arxiv.org/abs/2306.14002

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