Conformally Kähler structures

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Dunajski, Maciej, Gover, A. Rod
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915415201939456
author Dunajski, Maciej
Gover, A. Rod
author_facet Dunajski, Maciej
Gover, A. Rod
contents We establish a one-to-one correspondence between Kähler metrics in a given conformal class and parallel sections of a certain vector bundle with conformally invariant connection, where the parallel sections satisfy a set of non--linear algebraic constraints that we describe. The vector bundle captures 2-form prolongations and is isomorphic to $Λ^3(\cT)$, where ${\cT}$ is the tractor bundle of conformal geometry, but the resulting connection differs from the normal tractor connection by curvature terms. Our analysis leads to a set of obstructions for a Riemannian metric to be conformal to a Kähler metric. In particular we find an explicit algebraic condition for a Weyl tensor which must hold if there exists a conformal Killing-Yano tensor, which is a necessary condition for a metric to be conformal to Kähler. This gives an invariant characterisation of algebraically special Riemannian metrics of type $D$ in dimensions higher than four.
format Preprint
id arxiv_https___arxiv_org_abs_2409_17347
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Conformally Kähler structures
Dunajski, Maciej
Gover, A. Rod
Differential Geometry
Mathematical Physics
We establish a one-to-one correspondence between Kähler metrics in a given conformal class and parallel sections of a certain vector bundle with conformally invariant connection, where the parallel sections satisfy a set of non--linear algebraic constraints that we describe. The vector bundle captures 2-form prolongations and is isomorphic to $Λ^3(\cT)$, where ${\cT}$ is the tractor bundle of conformal geometry, but the resulting connection differs from the normal tractor connection by curvature terms. Our analysis leads to a set of obstructions for a Riemannian metric to be conformal to a Kähler metric. In particular we find an explicit algebraic condition for a Weyl tensor which must hold if there exists a conformal Killing-Yano tensor, which is a necessary condition for a metric to be conformal to Kähler. This gives an invariant characterisation of algebraically special Riemannian metrics of type $D$ in dimensions higher than four.
title Conformally Kähler structures
topic Differential Geometry
Mathematical Physics
url https://arxiv.org/abs/2409.17347