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Obstructions to Deformations of DG Modules

Trina Armstrong·Ron Umble
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Abstract

Let k be a field and n > 0. There exists a DG k-module (V,d) and various approximations d + t d_1 + t^2 d_2 + ... + t^n d_n to a differential on V[[t]], one of which is a non-trivial deformation, another is obstructed, and another is unobstructed at order n. The analogous problem in the category of k-algebras in characteristic zero remains a long-standing open question.

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Trina Armstrong, Ron Umble. 2001-06-27. Obstructions to Deformations of DG Modules. https://arxiv.org/abs/math/0106237

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