The Gerstenhaber structure on the Hochschild cohomology of a class of special biserial algebras

Abstract

We determine the Gerstenhaber structure on the Hochschild cohomology ring of a class of self-injective special biserial algebras. Each of these algebras is presented as a quotient of the path algebra of a certain quiver. In degree one, we show that the cohomology is isomorphic, as a Lie algebra, to a direct sum of copies of a subquotient of the Virasoro algebra. These copies share Virasoro degree 0 and commute otherwise. Finally, we describe the cohomology in degree nas a module over this Lie algebra by providing its decomposition as a direct sum of indecomposable modules.