Flat extensions of principal connections and the Chern-Simons $3$-form

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Čap, Andreas, Flood, Keegan J., Mettler, Thomas
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915816280162304
author Čap, Andreas
Flood, Keegan J.
Mettler, Thomas
author_facet Čap, Andreas
Flood, Keegan J.
Mettler, Thomas
contents We introduce the notion of a flat extension of a connection $θ$ on a principal bundle. Roughly speaking, $θ$ admits a flat extension if it arises as the pull-back of a component of a Maurer-Cartan form. For trivial bundles over closed oriented $3$-manifolds, we relate the existence of certain flat extensions to the vanishing of the Chern-Simons invariant associated with $θ$. As an application, we recover the obstruction of Chern-Simons for the existence of a conformal immersion of a Riemannian $3$-manifold into Euclidean $4$-space. In addition, we obtain corresponding statements for a Lorentzian $3$-manifold, as well as a global obstruction for the existence of an equiaffine immersion into $\mathbb{R}^4$ of a $3$-manifold that is equipped with a torsion-free connection preserving a volume form.
format Preprint
id arxiv_https___arxiv_org_abs_2409_12811
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Flat extensions of principal connections and the Chern-Simons $3$-form
Čap, Andreas
Flood, Keegan J.
Mettler, Thomas
Differential Geometry
Mathematical Physics
Geometric Topology
We introduce the notion of a flat extension of a connection $θ$ on a principal bundle. Roughly speaking, $θ$ admits a flat extension if it arises as the pull-back of a component of a Maurer-Cartan form. For trivial bundles over closed oriented $3$-manifolds, we relate the existence of certain flat extensions to the vanishing of the Chern-Simons invariant associated with $θ$. As an application, we recover the obstruction of Chern-Simons for the existence of a conformal immersion of a Riemannian $3$-manifold into Euclidean $4$-space. In addition, we obtain corresponding statements for a Lorentzian $3$-manifold, as well as a global obstruction for the existence of an equiaffine immersion into $\mathbb{R}^4$ of a $3$-manifold that is equipped with a torsion-free connection preserving a volume form.
title Flat extensions of principal connections and the Chern-Simons $3$-form
topic Differential Geometry
Mathematical Physics
Geometric Topology
url https://arxiv.org/abs/2409.12811