English

Gaps in Hochschild cohomology imply smoothness for commutative algebras

Commutative Algebra 2007-05-23 v2 Rings and Algebras

Abstract

The paper concerns Hochschild cohomology of a commutative algebra S, which is essentially of finite type over a commutative noetherian ring K and projective as a K-module, with coefficients in an S-module M. It is proved that vanishing of HH^n(S|K,M) in sufficiently long intervals imply the smoothness of S_q over K for all prime ideals q in the support of M. In particular, S is smooth if HH^n(S|K,S)=0 for (dim S+2) consecutive non-negative integers n.

Keywords

Cite

@article{arxiv.math/0412259,
  title  = {Gaps in Hochschild cohomology imply smoothness for commutative algebras},
  author = {Luchezar Avramov and Srikanth Iyengar},
  journal= {arXiv preprint arXiv:math/0412259},
  year   = {2007}
}

Comments

Minor revisions. To appear in Math. Res. Letters. 16 pages; available also at http://www.math.unl.edu/~siyengar