Planar pseudo-geodesics and totally umbilic submanifolds

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Markvorsen, Steen, Raffaelli, Matteo
Format: Preprint
Publié: 2021
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866911749534384128
author Markvorsen, Steen
Raffaelli, Matteo
author_facet Markvorsen, Steen
Raffaelli, Matteo
contents We study totally umbilic isometric immersions between Riemannian manifolds. First, we provide a novel characterization of the totally umbilic isometric immersions with parallel normalized mean curvature vector, i.e., those having nonzero mean curvature vector and such that the unit vector in the direction of the mean curvature vector is parallel in the normal bundle. Such characterization is based on a family of curves, called planar pseudo-geodesics, representing a natural extrinsic generalization of both geodesics and Riemannian circles: being planar, their Cartan development in the tangent space is planar in the ordinary sense; being pseudo-geodesics, their geodesic and normal curvatures satisfy a linear relation. We study these curves in detail and, in particular, establish their local existence and uniqueness. Moreover, in the case of codimension-one immersions, we prove the following statement: an isometric immersion $ι\colon M \hookrightarrow Q$ is totally umbilic if and only if the extrinsic shape of every geodesic of $M$ is planar. This extends a well-known result about surfaces in $\mathbb{R}^{3}$.
format Preprint
id arxiv_https___arxiv_org_abs_2107_10087
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Planar pseudo-geodesics and totally umbilic submanifolds
Markvorsen, Steen
Raffaelli, Matteo
Differential Geometry
53B25 (Primary) 53A04, 53C40, 53C42 (Secondary)
We study totally umbilic isometric immersions between Riemannian manifolds. First, we provide a novel characterization of the totally umbilic isometric immersions with parallel normalized mean curvature vector, i.e., those having nonzero mean curvature vector and such that the unit vector in the direction of the mean curvature vector is parallel in the normal bundle. Such characterization is based on a family of curves, called planar pseudo-geodesics, representing a natural extrinsic generalization of both geodesics and Riemannian circles: being planar, their Cartan development in the tangent space is planar in the ordinary sense; being pseudo-geodesics, their geodesic and normal curvatures satisfy a linear relation. We study these curves in detail and, in particular, establish their local existence and uniqueness. Moreover, in the case of codimension-one immersions, we prove the following statement: an isometric immersion $ι\colon M \hookrightarrow Q$ is totally umbilic if and only if the extrinsic shape of every geodesic of $M$ is planar. This extends a well-known result about surfaces in $\mathbb{R}^{3}$.
title Planar pseudo-geodesics and totally umbilic submanifolds
topic Differential Geometry
53B25 (Primary) 53A04, 53C40, 53C42 (Secondary)
url https://arxiv.org/abs/2107.10087