English

Compact convergence, deformation of the $L^2$-$\overline{\partial}$-complex and canonical $K$-homology classes

Differential Geometry 2024-06-18 v2 Complex Variables K-Theory and Homology

Abstract

Let (X,γ)(X,\gamma) be a compact, irreducible Hermitian complex space of complex dimension mm and with dim(sing(X))=0\mathrm{dim}(\mathrm{sing}(X))=0. Let (F,τ)X(F,\tau)\rightarrow X be a Hermitian holomorphic vector bundle over XX and let us denote with ðF,m,abs\overline{\eth}_{F,m,\mathrm{abs}} the rolled-up operator of the maximal L2L^2-\overline{\partial} complex of FF-valued (m,)(m,\bullet)-forms. Let π:MX\pi:M\rightarrow X be a resolution of singularities, gg a metric on MM, E:=πFE:=\pi^*F and ρ:=πτ\rho:=\pi^*\tau. In this paper, under quite general assumptions on τ\tau, we prove the following equality of analytic KK-homology classes [ðF,m,abs]=π[ðE,m][\overline{\eth}_{F,m,\mathrm{abs}}]=\pi_*[\overline{\eth}_{E,m}], with ðE,m\overline{\eth}_{E,m} the rolled-up operator of the L2L^2-\overline{\partial} complex of EE-valued (m,)(m,\bullet)-forms on MM. Our proof is based on functional analytic techniques developed in \cite{KuSh} and provides an explicit homotopy between the even unbounded Fredholm modules induced by ðF,m,abs\overline{\eth}_{F,m,\mathrm{abs}} and ðE,m\overline{\eth}_{E,m}.

Keywords

Cite

@article{arxiv.2308.12667,
  title  = {Compact convergence, deformation of the $L^2$-$\overline{\partial}$-complex and canonical $K$-homology classes},
  author = {Francesco Bei},
  journal= {arXiv preprint arXiv:2308.12667},
  year   = {2024}
}

Comments

Final version. To appear on J. Noncommut. Geom