Uniqueness of -structures and Hochschild cohomology
arXiv:0909.3222 · doi:10.2140/agt.2011.11.107
Abstract
This paper investigates if a differential graded algebra can have more than one -structure extending the given differential graded algebra structure. We give a sufficient condition for uniqueness of such an -structure up to quasi-isomorphism using Hochschild cohomology. We then extend this condition to Sagave's notion of derived -algebras after introducing a notion of Hochschild cohomology that applies to this.
The paper has been rearranged and the results are now formulated in terms of a filtration of the Hochschild cohomology groups. To appear in Algebraic and Geometric Topology