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arXiv · 1604.06507

A little bit of extra functoriality for Ext and the computation of the Gerstenhaber bracket

Mariano Suárez-Álvarez
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Abstract

We show that the action of the Lie algebra HH^1(A) of outer derivations of an associative algebra A on the Hochschild cohomology HH^*(A) of A given by the Gerstenhaber bracket can be computed in terms of an arbitrary projective resolution of A as an A-bimodule, without having recourse to comparison maps between the resolution and the bar resolution.

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Mariano Suárez-Álvarez. 2016-04-21. A little bit of extra functoriality for Ext and the computation of the Gerstenhaber bracket. https://doi.org/10.1016/j.jpaa.2016.10.015

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