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ON THE C-PROJECTIVE VECTOR FIELDS ON RANDERS SPACES

  • Rafie-Rad, Mehdi (Department of Mathematics Faculty of Mathematical Sciences University of Mazandaran) ;
  • Shirafkan, Azadeh (Department of Mathematics Faculty of Mathematical Sciences University of Mazandaran)
  • Received : 2019.08.08
  • Accepted : 2020.02.19
  • Published : 2020.07.01

Abstract

A characterization of the C-projective vector fields on a Randers space is presented in terms of 𝚵-curvature. It is proved that the 𝚵-curvature is invariant for C-projective vector fields. The dimension of the algebra of the C-projective vector fields on an n-dimensional Randers space is at most n(n + 2). The generalized Funk metrics on the n-dimensional Euclidean unit ball 𝔹n(1) are shown to be explicit examples of the Randers metrics with a C-projective algebra of maximum dimension n(n+2). Then, it is also proved that an n-dimensional Randers space has a C-projective algebra of maximum dimension n(n + 2) if and only if it is locally Minkowskian or (up to re-scaling) locally isometric to the generalized Funk metric. A new projective invariant is also introduced.

Keywords

References

  1. H. Akbar-Zadeh, Champ de vecteurs projectifs sur le fibre unitaire, J. Math. Pures Appl. (9) 65 (1986), no. 1, 47-79.
  2. D. Bao and Z. Shen, Finsler metrics of constant positive curvature on the Lie group $S^3$, J. London Math. Soc. (2) 66 (2002), no. 2, 453-467. https://doi.org/10.1112/S0024610702003344
  3. X. Chen, X. Mo, and Z. Shen, On the flag curvature of Finsler metrics of scalar curvature, J. London Math. Soc. (2) 68 (2003), no. 3, 762-780. https://doi.org/10.1112/S0024610703004599
  4. B. Najafi and A. Tayebi, A new quantity in Finsler geometry, C. R. Math. Acad. Sci. Paris 349 (2011), no. 1-2, 81-83. https://doi.org/10.1016/j.crma.2010.11.015
  5. B. Najafi and A. Tayebi, Weakly stretch Finsler metrics, Publ. Math. Debrecen 91 (2017), no. 3-4, 441-454. https://doi.org/10.5486/pmd.2017.7761
  6. B. Najafi and A. Tayebi, Some curvature properties of (${\alpha},{\beta}$)-metrics, Bull. Math. Soc. Sci. Math. Roumanie (N.S.) 60(108) (2017), no. 3, 277-291.
  7. M. Rafie-Rad, Some new characterizations of projective Randers metrics with constant S-curvature, J. Geom. Phys. 62 (2012), no. 2, 272-278. https://doi.org/10.1016/j.geomphys.2011.10.006
  8. M. Rafie-Rad, Special projective Lichnerowicz-Obata theorem for Randers spaces, C. R. Math. Acad. Sci. Paris 351 (2013), no. 23-24, 927-930. https://doi.org/10.1016/j.crma.2013.10.012
  9. M. Rafie-Rad and B. Rezaei, On the projective algebra of Randers metrics of constant flag curvature, SIGMA Symmetry Integrability Geom. Methods Appl. 7 (2011), Paper 085, 12 pp. https://doi.org/10.3842/SIGMA.2011.085
  10. M. Rafie-Rad and B. Rezaei, On the projective Randers metrics, C. R. Math. Acad. Sci. Paris 350 (2012), no. 5-6, 281-283. https://doi.org/10.1016/j.crma.2012.02.010
  11. B. Shen, Vanishing of projective vector fields on compact Finsler manifolds, J. Korean Math. Soc. 55 (2018), no. 1, 1-16. https://doi.org/10.4134/JKMS.j160619
  12. Z. Shen, Differential Geometry of Spray and Finsler Spaces, Kluwer Academic Publishers, Dordrecht, 2001. https://doi.org/10.1007/978-94-015-9727-2
  13. Z. Shen, On some non-Riemannian quantities in Finsler geometry, Canad. Math. Bull. 56 (2013), no. 1, 184-193. https://doi.org/10.4153/CMB-2011-163-4
  14. Z. Shen and H. Xing, On Randers metrics with isotropic S-curvature, Acta Math. Sin. (Engl. Ser.) 24 (2008), no. 5, 789-796. https://doi.org/10.1007/s10114-007-5194-0
  15. D. Tang, On the non-Riemannian quantity H in Finsler geometry, Differential Geom. Appl. 29 (2011), no. 2, 207-213. https://doi.org/10.1016/j.difgeo.2010.12.002
  16. A. Tayebi, On the class of generalized Landsberg manifolds, Period. Math. Hungar. 72 (2016), no. 1, 29-36. https://doi.org/10.1007/s10998-015-0108-x
  17. A. Tayebi, On generalized 4-th root metrics of isotropic scalar curvature, Math. Slovaca 68 (2018), no. 4, 907-928. https://doi.org/10.1515/ms-2017-0154
  18. A. Tayebi, On 4-th root metrics of isotropic scalar curvature, Math. Slovaca 70 (2020), no. 1, 161-172. https://doi.org/10.1515/ms-2017-0341
  19. A. Tayebi and M. Barzegari, Generalized Berwald spaces with (${\alpha},{\beta}$)-metrics, Indag. Math. (N.S.) 27 (2016), no. 3, 670-683. https://doi.org/10.1016/j.indag.2016.01.002
  20. A. Tayebi and M. Razgordani, On H-curvature of (${\alpha},{\beta}$)-metrics, Turkish J. Math. 44 (2020), 207-222. https://doi.org/10.3906/mat-1805-130
  21. A. Tayebi and T. Tabatabaeifar, Unicorn metrics with almost vanishing H- and $\Xi$-curvatures, Turkish J. Math. 41 (2017), no. 4, 998-1008+5 pp. https://doi.org/10.3906/mat-1606-35
  22. K. Yano, The Theory of Lie Derivatives and Its Applications, North-Holland Publishing Co., Amsterdam, 1957.