More counterexamples to Happel's question and Snashall-Solberg's conjecture

Yunge Xu; Chao Zhang

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arXiv · 1109.3956

More counterexamples to Happel's question and Snashall-Solberg's conjecture

Yunge Xu·Chao Zhang

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Abstract

In this paper we provide more counterexamples to Happel's question and Snashall-Solberg's conjecture which generalize many counterexamples to these conjectures studied in the literature. In particular, we show that a family of $\mathbb{Z}_n\times \mathbb{Z}_n$-Galois covering algebras of quantized exterior algebra $A_q$ in two variables answer negatively to Happel's question, and meanwhile, the one-point coextensions of $\mathbb{Z}_n$ and $\mathbb{Z}_n\times \mathbb{Z}_m$-Galois covering algebras of $A_q$ negate the Snashall-Solberg's conjecture.

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BibTeX RIS

Yunge Xu, Chao Zhang. 2011-09-19. More counterexamples to Happel's question and Snashall-Solberg's conjecture. https://arxiv.org/abs/1109.3956

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