On the volume of a unit vector field in 3 dimensions via calibrations

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Albuquerque, Rui
Format: Preprint
Published: 2022
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908595697745920
author Albuquerque, Rui
author_facet Albuquerque, Rui
contents We give a new proof of the well-known result that the minimal volume vector fields on $\mathbb{S}^3(r)$ are the Hopf vector fields. Such proof relies again on calibration theory, arising here from a systematic point of view given by a natural source of differential forms. Our results serve in particular for all $r$. A classification of relevant calibrations on $T^1M$ for every oriented 3-manifold $M$ of constant sectional curvature is given, continuing the study of the \textit{usual} fundamental differential system of Riemannian geometry. Showing applications of this differential system is also one of the purposes of this article. We deduce new properties of the geodesic flow vector field of space forms, which interacts with the solutions of the minimal volume problem both in elliptic and hyperbolic geometry, in any dimension. The solution -- unknown -- for the hyperbolic case in 3-dimensions being most dependent on the homology class of the domain and boundary values of the vector fields. This is illustrated with a noteworthy example which ironically works just for curvature $-1$.
format Preprint
id arxiv_https___arxiv_org_abs_2207_08761
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle On the volume of a unit vector field in 3 dimensions via calibrations
Albuquerque, Rui
Differential Geometry
53C20, 53C35, 53C38, 53D25, Secondary: 53C17, 58A15
We give a new proof of the well-known result that the minimal volume vector fields on $\mathbb{S}^3(r)$ are the Hopf vector fields. Such proof relies again on calibration theory, arising here from a systematic point of view given by a natural source of differential forms. Our results serve in particular for all $r$. A classification of relevant calibrations on $T^1M$ for every oriented 3-manifold $M$ of constant sectional curvature is given, continuing the study of the \textit{usual} fundamental differential system of Riemannian geometry. Showing applications of this differential system is also one of the purposes of this article. We deduce new properties of the geodesic flow vector field of space forms, which interacts with the solutions of the minimal volume problem both in elliptic and hyperbolic geometry, in any dimension. The solution -- unknown -- for the hyperbolic case in 3-dimensions being most dependent on the homology class of the domain and boundary values of the vector fields. This is illustrated with a noteworthy example which ironically works just for curvature $-1$.
title On the volume of a unit vector field in 3 dimensions via calibrations
topic Differential Geometry
53C20, 53C35, 53C38, 53D25, Secondary: 53C17, 58A15
url https://arxiv.org/abs/2207.08761