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arXiv · 2608.17706

A Symmetric Counterexample to the Snashall--Solberg Conjecture

Kai Wang·Guodong Zhou
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Abstract

It is shown that the trivial extension of the Xu--Snashall algebra is a symmetric counterexample to the Snashall--Solberg conjecture, which states that the Hochschild cohomology ring of a finite-dimensional algebra modulo nilpotence is a finitely generated algebra. To the best of our knowledge, this is the first known selfinjective counterexample.

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Kai Wang, Guodong Zhou. 2026-08-18. A Symmetric Counterexample to the Snashall--Solberg Conjecture. https://arxiv.org/abs/2608.17706

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