English

Functoriality of HKR isomorphisms

Algebraic Geometry 2020-10-22 v2

Abstract

For a closed embedding of smooth schemes XSX\hookrightarrow S with a fixed first order splitting, one can construct HKR isomorphisms between the derived scheme X×SRXX\times^R_S X and the total space of the shifted normal bundle NX/S[1]\mathbb{N}_{X/S}[-1], due to Arinkin-C\u{a}ld\u{a}raru, Arinkin-C\u{a}ld\u{a}raru-Hablicsek, and Grivaux. In this paper, we study functoriality property of the HKR isomorphisms for a sequence of closed embeddings XYSX\hookrightarrow Y\hookrightarrow S. The HKR isomorphism is functorial when a certain cohomology class, which we call the Bass-Quillen class, vanishes. We obtain Lie theoretic interpretations for the HKR isomorphisms and for the Bass-Quillen class as well.

Cite

@article{arxiv.2002.00017,
  title  = {Functoriality of HKR isomorphisms},
  author = {Shengyuan Huang},
  journal= {arXiv preprint arXiv:2002.00017},
  year   = {2020}
}
R2 v1 2026-06-23T13:27:06.942Z