Distinguishing derived equivalence classes using the second Hochschild cohomology group
Tom 121 / 2010
Colloquium Mathematicum 121 (2010), 285-294
MSC: Primary 16E40, 18E30; Secondary 16D50, 16G60.
DOI: 10.4064/cm121-2-11
Streszczenie
We study the second Hochschild cohomology group of the preprojective algebra of type $D_4$ over an algebraically closed field $K$ of characteristic 2. We also calculate the second Hochschild cohomology group of a non-standard algebra which arises as a socle deformation of this preprojective algebra and so show that the two algebras are not derived equivalent. This answers a question raised by Holm and Skowroński.
