A short note on deformations of (strongly) Gorenstein-projective modules over the dual numbers
Jose A. Velez-Marulanda, Hector Suarez
Abstract
Let $\mathbf{k}$ be a field of arbitrary characteristic, and let $Λ$ be a finite dimensional $\mathbf{k}$-algebra. In this short note we prove that if $V$ is a finitely generated strongly Gorenstein-projective left $Λ$-module whose stable endomorphism ring $\underline{\mathrm{End}}_Λ(V)$ is isomorphic to $\mathbf{k}$, then $V$ has an universal deformation ring $R(Λ,V)$ isomorphic to the ring of dual numbers $\mathbf{k}[ε]$ with $ε^2=0$. As a consequence, we obtain the following result. Assume that $Q$ is a finite connected acyclic quiver, let $\mathbf{k} Q$ be the corresponding path algebra and let $Λ= \mathbf{k} Q[ε] = \mathbf{k} Q\otimes_{\mathbf{k}} \mathbf{k}[ε]$. If $V$ is a finitely generated Gorenstein-projective left $Λ$-module with $\underline{\mathrm{End}}_Λ(V)=\mathbf{k}$, then $V$ has an universal deformation ring $R(Λ,V)$ isomorphic to $\mathbf{k}[ε]
