Universal deformation rings and derived equivalences
Shengyong Pan
TL;DR
The paper addresses the invariance of versal deformation rings under stable functors arising from derived and Morita-type equivalences for Gorenstein-projective modules over finite dimensional $k$-algebras. It develops a stable functor framework for non-negative derived functors and applies it to deformation theory, proving isomorphisms $R(A,V)\, ext{≅}\, R(B,ar{F}(V))$ when transferring through derived equivalences, and extends these results to stable equivalences of Morita type. The main contributions include generalizing Veléz-Marulanda-type results to non-Gorenstein and singular Morita-type settings, and establishing preservation of versal deformation rings under stable Morita-type equivalences. Overall, the work strengthens deformation-theoretic invariants across a broad class of equivalences, enabling transfer of deformation information between derived- or stably-equivalent algebras.
Abstract
In this paper, we show that stable functors of derived equivalences preserve the isomorphism classes of versal deformation rings of finitely generated Gorenstein-projective modules over finite dimensional $k$-algebras. Then we generalize Veléz-Marulanda's result \cite{V} in the case of singular equivalences of Morita type with levels for Gorenstein algebras. Moreover, we also prove that stable equivalences of Morita type preserve the isomorphism classes of versal deformation rings of finitely generated Gorenstein-projective modules over finite dimensional $k$-algebras.
