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arXiv · 1304.7117

Homological smoothness and deformations of generalized Weyl algebras

Liyu Liu
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Abstract

It is an immediate conclusion from Bavula's papers \cite{Bavula:GWA-def}, \cite{Bavula:GWA-tensor-product} that if a generalized Weyl algebra $A=\kk[z;\lambda,\eta,\varphi(z)]$ is homologically smooth, then the polynomial $\varphi(z)$ has no multiple roots. We prove in this paper that the converse is also true. Moreover, formal deformations of $A$ are studied when $\kk$ is of characteristic zero.

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Liyu Liu. 2013-04-26. Homological smoothness and deformations of generalized Weyl algebras. https://arxiv.org/abs/1304.7117

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