Marcos M. Alexandrino, Fernando M. Escobosa, Marcelo K. Inagaki
{"title":"Traveling along horizontal broken geodesics of a homogeneous Finsler submersion","authors":"Marcos M. Alexandrino, Fernando M. Escobosa, Marcelo K. Inagaki","doi":"10.1016/j.difgeo.2023.102106","DOIUrl":null,"url":null,"abstract":"<div><p><span>In this paper, we discuss how to travel along horizontal broken geodesics of a homogeneous Finsler submersion<span>, i.e., we study, what in Riemannian geometry was called by Wilking, the dual leaves. More precisely, we investigate the attainable sets </span></span><span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>q</mi></mrow></msub><mo>(</mo><mi>C</mi><mo>)</mo></math></span> of the set of analytic vector fields <span><math><mi>C</mi></math></span> determined by the family of horizontal unit geodesic vector fields <span><math><mi>C</mi></math></span> to the fibers <span><math><mi>F</mi><mo>=</mo><mo>{</mo><msup><mrow><mi>ρ</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>(</mo><mi>c</mi><mo>)</mo><mo>}</mo></math></span> of a homogeneous analytic Finsler submersion <span><math><mi>ρ</mi><mo>:</mo><mi>M</mi><mo>→</mo><mi>B</mi></math></span>. Since reverse of geodesics don't need to be geodesics in Finsler geometry, one can have examples on non compact Finsler manifolds <em>M</em><span> where the attainable sets (the dual leaves) are no longer orbits or even submanifolds. Nevertheless we prove that, when </span><em>M</em> is compact and the orbits of <span><math><mi>C</mi></math></span> are embedded, then the attainable sets coincide with the orbits. Furthermore, if the flag curvature is positive then <em>M</em> coincides with the attainable set of each point. In other words, fixed two points of <em>M</em>, one can travel from one point to the other along horizontal broken geodesics.</p><p>In addition, we show that each orbit <span><math><mi>O</mi><mo>(</mo><mi>q</mi><mo>)</mo></math></span> of <span><math><mi>C</mi></math></span> associated to a singular Finsler foliation coincides with <em>M</em><span><span>, when the flag curvature is positive, i.e., we prove Wilking's result in Finsler context. In particular we review Wilking's transversal </span>Jacobi fields in Finsler case.</span></p></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"93 ","pages":"Article 102106"},"PeriodicalIF":0.6000,"publicationDate":"2024-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Differential Geometry and its Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0926224523001328","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
In this paper, we discuss how to travel along horizontal broken geodesics of a homogeneous Finsler submersion, i.e., we study, what in Riemannian geometry was called by Wilking, the dual leaves. More precisely, we investigate the attainable sets of the set of analytic vector fields determined by the family of horizontal unit geodesic vector fields to the fibers of a homogeneous analytic Finsler submersion . Since reverse of geodesics don't need to be geodesics in Finsler geometry, one can have examples on non compact Finsler manifolds M where the attainable sets (the dual leaves) are no longer orbits or even submanifolds. Nevertheless we prove that, when M is compact and the orbits of are embedded, then the attainable sets coincide with the orbits. Furthermore, if the flag curvature is positive then M coincides with the attainable set of each point. In other words, fixed two points of M, one can travel from one point to the other along horizontal broken geodesics.
In addition, we show that each orbit of associated to a singular Finsler foliation coincides with M, when the flag curvature is positive, i.e., we prove Wilking's result in Finsler context. In particular we review Wilking's transversal Jacobi fields in Finsler case.
在本文中,我们将讨论如何沿着同质芬斯勒潜流的水平破碎大地线行进,即研究黎曼几何中威尔金所谓的对偶叶。更确切地说,我们研究的是同质解析芬斯勒潜影 ρ:M→B 的纤维 F={ρ-1(c)} 的水平单位大地向量场 C 族决定的解析向量场 C 集的可实现集 Aq(C)。由于测地线的反向在芬斯勒几何中不一定是测地线,因此我们可以在非紧凑芬斯勒流形 M 上举例说明可达到的集合(对偶叶)不再是轨道,甚至不再是子流形。然而,我们证明,当 M 紧凑且 C 的轨道嵌入时,可实现集与轨道重合。此外,如果旗曲率为正,那么 M 与每个点的可诣集重合。此外,我们还证明了当旗曲率为正时,与奇异芬斯勒折线相关联的 C 的每个轨道 O(q) 与 M 重合,也就是说,我们证明了芬斯勒背景下的威尔金结果。我们特别回顾了 Wilking 在 Finsler 情况下的横向雅可比场。
期刊介绍:
Differential Geometry and its Applications publishes original research papers and survey papers in differential geometry and in all interdisciplinary areas in mathematics which use differential geometric methods and investigate geometrical structures. The following main areas are covered: differential equations on manifolds, global analysis, Lie groups, local and global differential geometry, the calculus of variations on manifolds, topology of manifolds, and mathematical physics.