English

Smoothness of equivariant derived categories

K-Theory and Homology 2018-05-16 v3 Algebraic Geometry Representation Theory

Abstract

We introduce the notion of (homological) G-smoothness for a complex G-variety X, where G is a connected affine algebraic group. This is based on the notion of smoothness for dg algebras and uses a suitable enhancement of the G-equivariant derived category of X. If there are only finitely many G-orbits and all stabilizers are connected, we show that X is G-smooth if and only if all orbits O satisfy H^*(O; R)=R. On the way we prove several results concerning smoothness of dg categories over a graded commutative dg ring.

Keywords

Cite

@article{arxiv.1205.3132,
  title  = {Smoothness of equivariant derived categories},
  author = {Valery A. Lunts and Olaf M. Schnürer},
  journal= {arXiv preprint arXiv:1205.3132},
  year   = {2018}
}

Comments

64 pages, Remark 4.7 improved

R2 v1 2026-06-21T21:03:46.934Z