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arXiv · 2202.01199

The Ext-algebra for infinitesimal deformations

María Julia Redondo·Lucrecia Román·Fiorela Rossi Bertone
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Abstract

Let $f$ be a Hochschild $2$-cocycle and let $A_f$ be an infinitesimal deformation of an associative finite dimensional algebra $A$ over an algebraically closed field $\Bbbk$. We investigate the algebra structure of the Ext-algebra of $A_f$ and, under some conditions on $f$, we describe it in terms of the Ext-algebra of $A$. We achieve this description by getting an explicit construction of minimal projective resolutions in $\mod A_f$.

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María Julia Redondo, Lucrecia Román, Fiorela Rossi Bertone. 2022-02-02. The Ext-algebra for infinitesimal deformations. https://arxiv.org/abs/2202.01199

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