English

On the Chern-Ricci form of a twisted almost K\"{a}hler structure

Differential Geometry 2026-05-05 v2

Abstract

Let (M,g,J,ω)(M,g,J,\omega) be an almost K\"{a}hler manifold. For any smooth function ff on MM, one can associate an automorphism ψ\mboxAut(TM)\psi\in \mbox{Aut}(TM) for which the K\"{a}hler form is invariant. Using ψ\psi, one can ``twist" the metric gg and almost complex structure JJ to obtain a new almost K\"{a}hler structure (gψ,Jψ,ω)(g^\psi,J^\psi,\omega) on MM. Let D~\widetilde{D} denote the Chern connection of (gψ,Jψ,ω)(g^\psi,J^\psi,\omega) and let K1K^{-1} denote the anti-canonical bundle of (TM,Jψ)(TM,J^\psi). In the current paper, we give an explicit formula for the local connection 1-form α\alpha associated to the pair (K1,D~)(K^{-1},\widetilde{D}). The Chern-Ricci form of (gψ,Jψ,ω)(g^\psi,J^\psi,\omega) is then ρD~=dα\rho_{\widetilde{D}}=-d\alpha. We note that under certain conditions the aforementioned formula assumes a simpler form when applied to the calculation of α\alpha. We illustrate this with some examples.

Keywords

Cite

@article{arxiv.2604.06344,
  title  = {On the Chern-Ricci form of a twisted almost K\"{a}hler structure},
  author = {David N. Pham and Fei Ye},
  journal= {arXiv preprint arXiv:2604.06344},
  year   = {2026}
}

Comments

16 pages, section 1 revised