Geodesic orbit Finsler spaces with K ≥ 0 and the (FP) condition
-
Ming Xu
Abstract
We study the interaction between the g.o. property and certain flag curvature conditions. A Finsler manifold is called g.o. if each constant speed geodesic is the orbit of a one-parameter subgroup. Besides the non-negatively curved condition, we also consider the condition (FP) for the flag curvature, i.e. in any flag we find a flag pole such that the flag curvature is positive. By our main theorem, if a g.o. Finsler space (M, F) has non-negative flag curvature and satisfies (FP), then M is compact. If M = G/H where G has a compact Lie algebra, then the rank inequality rk 𝔤 ≤ rk 𝔥+1 holds. As an application,we prove that any even-dimensional g.o. Finsler space which has non-negative flag curvature and satisfies (FP) is a smooth coset space admitting a positively curved homogeneous Riemannian or Finsler metric.
Funding statement: This paper is supported by Beijing Natural Science Foundation (No. Z180004), NSFC (No. 11771331, No. 11821101), Capacity Building for Sci-Tech Innovation —+Fundamental Scientific Research Funds (No. KM201910028021).
Acknowledgements
The author sincerely thanks Fernando Galaz-Garcia, Yuri G. Nikonorov and Wolfgang Ziller for helpful discussions.
References
[1] D. N. Akhiezer, E. B. Vinberg, Weakly symmetric spaces and spherical varieties. Transform. Groups 4 (1999), 3–24. MR1669186 Zbl 0916.5302410.1007/BF01236659Suche in Google Scholar
[2] D. Alekseevsky, A. Arvanitoyeorgos, Riemannian flag manifolds with homogeneous geodesics. Trans. Amer. Math. Soc. 359 (2007), 3769–3789. MR2302514 Zbl 1148.5303810.1090/S0002-9947-07-04277-8Suche in Google Scholar
[3] D. V. Alekseevsky, Y. G. Nikonorov, Compact Riemannian manifolds with homogeneous geodesics. SIGMA Symmetry Integrability Geom. Methods Appl. 5 (2009), Paper 093, 16 pages. MR2559668 Zbl 1189.5304710.3842/SIGMA.2009.093Suche in Google Scholar
[4] J. C. Álvarez Paiva, C. E. Durán, Isometric submersions of Finsler manifolds. Proc. Amer. Math. Soc. 129 (2001), 2409–2417. MR1823926 Zbl 0992.5305510.1090/S0002-9939-01-05910-XSuche in Google Scholar
[5] A. Arvanitoyeorgos, Y. Wang, Homogeneous geodesics in generalized Wallach spaces. Bull. Belg. Math. Soc. Simon Stevin 24 (2017), 257–270. MR3694002 Zbl 1385.5302110.36045/bbms/1503453709Suche in Google Scholar
[6] D. Bao, S.-S. Chern, Z. Shen, An introduction to Riemann-Finsler geometry. Springer 2000. MR1747675 Zbl 0954.5300110.1007/978-1-4612-1268-3Suche in Google Scholar
[7] V. N. Berestovskiı̌, Y. G. Nikonorov, Generalized normal homogeneous Riemannian metrics on spheres and projective spaces. Ann. Global Anal. Geom. 45 (2014), 167–196. MR3170521 Zbl 1410.5305410.1007/s10455-013-9393-xSuche in Google Scholar
[8] V. N. Berestovskiı̌, Y. G. Nikonorov, On homogeneous geodesics and weakly symmetric spaces. Ann. Global Anal. Geom. 55 (2019), 575–589. MR3936234 Zbl 1414.5302510.1007/s10455-018-9641-1Suche in Google Scholar
[9] M. Berger, Les variétés riemanniènes homogènes simplement connexes de dimension impair à courbure strictement positive. Int. J. Pure Appl. Math. 55 (1976), 47–68.Suche in Google Scholar
[10] S.-S. Chern, Z. Shen, Riemann-Finsler geometry, volume 6 of Nankai Tracts in Mathematics. World Scientific Publishing Co., Hackensack, NJ 2005. MR2169595 Zbl 1085.5306610.1142/5263Suche in Google Scholar
[11] S. Deng, Homogeneous Finsler spaces. Springer 2012. MR2962626 Zbl 1253.5300210.1007/978-1-4614-4244-8Suche in Google Scholar
[12] S. Deng, Z. Hu, Curvatures of homogeneous Randers spaces. Adv. Math. 240 (2013), 194–226. MR3046307 Zbl 1281.5307510.1016/j.aim.2013.02.002Suche in Google Scholar
[13] S. Deng, M. Xu, Recent progress on homogeneous Finsler spaces with positive curvature. Eur. J. Math. 3 (2017), 974–999. MR3736794 Zbl 1381.5314010.1007/s40879-017-0148-2Suche in Google Scholar
[14] Z. Dušek, O. Kowalski, S. v. Nikčević, New examples of Riemannian g.o. manifolds in dimension 7. Differential Geom. Appl. 21 (2004), 65–78. MR2067459 Zbl 1050.2201110.1016/j.difgeo.2004.03.006Suche in Google Scholar
[15] C. S. Gordon, Homogeneous Riemannian manifolds whose geodesics are orbits. In: Topics in geometry, volume 20 of Progr. Nonlinear Differential Equations Appl., 155–174, Birkhäuser Boston, Boston, MA 1996. MR1390313 Zbl 0861.5305210.1007/978-1-4612-2432-7_4Suche in Google Scholar
[16] C. S. Gordon, Y. G. Nikonorov, Geodesic orbit Riemannian structures on ℝnJ. Geom. Phys. 134 (2018), 235–243. MR3886938 Zbl 1407.5303210.1016/j.geomphys.2018.08.018Suche in Google Scholar
[17] S. Helgason, Differential geometry, Lie groups, and symmetric spaces, volume 80 of Pure and Applied Mathematics. Academic Press 1978. MR514561 Zbl 0451.53038Suche in Google Scholar
[18] J. Hilgert, K.-H. Neeb, Structure and geometry of Lie groups. Springer 2012. MR3025417 Zbl 1229.2200810.1007/978-0-387-84794-8Suche in Google Scholar
[19] L. Huang, On the fundamental equations of homogeneous Finsler spaces. Differential Geom. Appl. 40 (2015), 187–208. MR3333102 Zbl 1320.5302710.1016/j.difgeo.2014.12.009Suche in Google Scholar
[20] L. Huang, Ricci curvatures of left invariant Finsler metrics on Lie groups. Israel J. Math. 207 (2015), 783–792. MR3359718 Zbl 1325.5309710.1007/s11856-015-1161-0Suche in Google Scholar
[21] L. Huang, Flag curvatures of homogeneous Finsler spaces. Eur. J. Math. 3 (2017), 1000–1029. MR3736795 Zbl 1381.5314310.1007/s40879-017-0157-1Suche in Google Scholar
[22] O. Kowalski, L. Vanhecke, Riemannian manifolds with homogeneous geodesics. Boll. Un. Mat. Ital. B (7) 5 (1991), 189–246. MR1110676 Zbl 0731.5304610.1142/9789814439381_0003Suche in Google Scholar
[23] Y. G. Nikonorov, Geodesic orbit Riemannian metrics on spheres. Vladikavkaz. Mat. Zh. 15 (2013), 67–76. MR3881073 Zbl 1293.53062Suche in Google Scholar
[24] Y. G. Nikonorov, On the structure of geodesic orbit Riemannian spaces. Ann. Global Anal. Geom. 52 (2017), 289–311. MR3711602 Zbl 1381.5308810.1007/s10455-017-9558-0Suche in Google Scholar
[25] Z. Shen, Lectures on Finsler geometry. World Scientific Publishing Co., Singapore 2001. MR1845637 Zbl 0974.5300210.1142/4619Suche in Google Scholar
[26] F. M. Valiev, Sharp estimates of sectional curvatures of homogeneous Riemannian metrics on Wallach spaces (Russian). Sibirsk. Mat. Zh. 20 (1979), 248–262, 457. English translation: Sib. Math. J. 20 (1979), 176–187. MR530489 Zbl 0433.5303510.1007/BF00970021Suche in Google Scholar
[27] N. R. Wallach, Compact homogeneous Riemannian manifolds with strictly positive curvature. Ann. of Math. (2) 96 (1972), 277–295. MR307122 Zbl 0261.5303310.2307/1970789Suche in Google Scholar
[28] M. Xu, Examples of flag-wise positively curved spaces. Differential Geom. Appl. 52 (2017), 42–50. MR3656420 Zbl 1369.5303410.1016/j.difgeo.2017.03.015Suche in Google Scholar
[29] M. Xu, Geodesic orbit spheres and constant curvature in Finsler geometry. Differential Geom. Appl. 61 (2018), 197–206. MR3856756 Zbl 1404.5309410.1016/j.difgeo.2018.07.002Suche in Google Scholar
[30] M. Xu, S. Deng, Normal homogeneous Finsler spaces. Transform. Groups 22 (2017), 1143–1183. MR3717227 Zbl 1385.5306510.1007/s00031-017-9428-7Suche in Google Scholar
[31] M. Xu, S. Deng, Rigidity of negatively curved geodesic orbit Finsler spaces. C. R. Math. Acad. Sci. Paris 355 (2017), 987–990. MR3709539 Zbl 1377.5306110.1016/j.crma.2017.09.003Suche in Google Scholar
[32] M. Xu, S. Deng, Homogeneous Finsler spaces and the flag-wise positively curved condition. Forum Math. 30 (2018), 1521–1537. MR3871459 Zbl 0699673010.1515/forum-2018-0130Suche in Google Scholar
[33] M. Xu, S. Deng, L. Huang, Z. Hu, Even-dimensional homogeneous Finsler spaces with positive flag curvature. Indiana Univ. Math. J. 66 (2017), 949–972. MR3663332 Zbl 1371.5304910.1512/iumj.2017.66.6040Suche in Google Scholar
[34] M. Xu, S. Deng, Z. Yan, Geodesic orbit Finsler metrics on Euclidean spaces. Preprint, 2018. arXiv:1807.02976v2 [math.DG]Suche in Google Scholar
[35] M. Xu, Y. G. Nikonorov, Algebraic properties of bounded Killing vector fields. Preprint, 2018. arXiv:1904.08710v2 [math.DG]Suche in Google Scholar
[36] M. Xu, L. Zhang, δ-homogeneity in Finsler geometry and the positive curvature problem. Osaka J. Math. 55 (2018), 177–194. MR3744979 Zbl 1390.53079Suche in Google Scholar
[37] M. Xu, W. Ziller, Reversible homogeneous Finsler metrics with positive flag curvature. Forum Math. 29 (2017), 1213–1226. MR3692034 Zbl 1375.5306810.1515/forum-2016-0173Suche in Google Scholar
[38] Z. Yan, S. Deng, Finsler spaces whose geodesics are orbits. Differential Geom. Appl. 36 (2014), 1–23. MR3262894 Zbl 1308.5311410.1016/j.difgeo.2014.06.006Suche in Google Scholar
© 2021 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- An 𝔽p2-maximal Wiman sextic and its automorphisms
- Pseudo-algebraic Ricci solitons on Einstein nilradicals
- The wobbly divisors of the moduli space of rank-2 vector bundles
- Symmetries of complex analytic vector fields with an essential singularity on the Riemann sphere
- Betti numbers and pseudoeffective cones in 2-Fano varieties
- The generating rank of a polar Grassmannian
- The Beckman–Quarles theorem via the triangle inequality
- On Huisman’s conjectures about unramified real curves
- Geodesic orbit Finsler spaces with K ≥ 0 and the (FP) condition
- On the Segre invariant for rank two vector bundles on ℙ2
- Lifting coarse homotopies
- How to construct all metric f-K-contact manifolds
- An extremum problem for the power moment of a convex polygon contained in a disc
- Sharply transitive sets in PGL2(K)
Artikel in diesem Heft
- Frontmatter
- An 𝔽p2-maximal Wiman sextic and its automorphisms
- Pseudo-algebraic Ricci solitons on Einstein nilradicals
- The wobbly divisors of the moduli space of rank-2 vector bundles
- Symmetries of complex analytic vector fields with an essential singularity on the Riemann sphere
- Betti numbers and pseudoeffective cones in 2-Fano varieties
- The generating rank of a polar Grassmannian
- The Beckman–Quarles theorem via the triangle inequality
- On Huisman’s conjectures about unramified real curves
- Geodesic orbit Finsler spaces with K ≥ 0 and the (FP) condition
- On the Segre invariant for rank two vector bundles on ℙ2
- Lifting coarse homotopies
- How to construct all metric f-K-contact manifolds
- An extremum problem for the power moment of a convex polygon contained in a disc
- Sharply transitive sets in PGL2(K)