Special biserial algebras with no outer derivations
arXiv:1107.5099 · doi:10.4064/cm125-1-6
Abstract
Let be a special biserial algebra over an algebraically closed field. We show that the first Hohchshild cohomology group of with coefficients in the bimodule vanishes if and only if is representation finite and simply connected (in the sense of Bongartz and Gabriel), if and only if the Euler characteristic of equals the number of indecomposable non uniserial projective injective -modules (up to isomorphism). Moreover, if this is the case, then all the higher Hochschild cohomology groups of vanish.
13 pages, submitted