English

Matrix Factorisation of Morse-Bott functions

Algebraic Geometry 2020-03-18 v2

Abstract

For a function WC[X]W\in \mathbb{C}[X] on a smooth algebraic variety XX with Morse-Bott critical locus YXY\subset X, Kapustin, Rozansky and Saulina suggest that the associated matrix factorisation category MF(X;W)\mathrm{MF}(X;W) should be equivalent to the differential graded category of 22-periodic coherent complexes on YY (with a topological twist from the normal bundle of YY). I confirm their conjecture in the special case when the first neighbourhood of YY in XX is split, and establish the corrected general statement. The answer involves the full Gerstenhaber structure on Hochschild cochains. This note was inspired by the failure of the conjecture, observed by Pomerleano and Preygel, when XX is a general one-parameter deformation of a K3K3 surface YY.

Keywords

Cite

@article{arxiv.1611.07057,
  title  = {Matrix Factorisation of Morse-Bott functions},
  author = {Constantin Teleman},
  journal= {arXiv preprint arXiv:1611.07057},
  year   = {2020}
}

Comments

10 pages. Added an appendix on curved formal deformations. Proofs clarified, references added, other minor corrections

R2 v1 2026-06-22T16:59:57.412Z