Generalized Berwald metrics

In this paper, we consider a class of Finsler metrics called generalized Berwald metrics which contains the class of Berwald metrics as a special case. We prove that every generalized Berwald metrics with non-zero scalar flag curvature or isotropic Berwald curvature is a Randers metric. Then we prove that on generalized Berwald metrics, the notions of generalized Landsberg and Landsberg curvatures are equivalent.

Generalized Berwald metrics

In this paper, we consider a class of Finsler metrics called generalized Berwald metrics which contains the class of Berwald metrics as a special case. We prove that every generalized Berwald metrics with non-zero scalar flag curvature or isotropic Berwald curvature is a Randers metric. Then we prove that on generalized Berwald metrics, the notions of generalized Landsberg and Landsberg curvatures are equivalent.

___

  • Antonelli, P. L.: Handbook of Finsler Geometry, Kluwer Academic Publishers, 2005.
  • Bejancu, A., Farran, H.: Generalized Landsberg Manifolds of scalar curvature, Bull. Korean Math. Soc. 37(3), –550 (2000).
  • Berwald, L.: ¨Uber Parallel¨ubertragung in R¨aumen mit allgemeiner Massbestimmung, Jber. Deutsch. Math.- Verein. 34, 213–220 (1926).
  • Chen, X., Shen, Z.: On Douglas Metrics, Publ. Math. Debrecen. 66, 503–512 (2005).
  • Chen, X., Shen, Z.: Randers metrics with special curvature properties, Osaka J. of Math. 40, 87–101 (2003).
  • Ichijy¯o, Y.: Finsler manifolds modelled on a Minkowski space, J. Math. Kyoto Univ. 16, 639–652 (1976).
  • Matsumoto, M.: On C-reducible Finsler spaces, Tensor, N. S. 24, 29–37 (1972).
  • Matsumoto, M.: On Finsler spaces with Randers metric and special forms of important tensors, J. Math. Kyoto Univ. 14, 477–498 (1974).
  • Matsumoto, M., Shimada, H.: On Finsler spaces with the curvature tensors Phijkand Shijksatisfying special conditions, Rep. Math. Phys. 12, 77–87 (1977).
  • Matsumoto, M., H¯oj¯o, S.: A conclusive theorem on C-reducible Finsler spaces, Tensor. N. S. 32, 225–230 (1978).
  • NajaŞ, B., Shen, Z., Tayebi, A.: Finsler metrics of scalar flag curvature with special non-Riemannian curvature properties, Geom. Dedicata. 131, 87–97 (2008).
  • NajaŞ, B., Tayebi, A., Rezaei, M. M.: General relatively isotropic L-curvature Finsler manifolds, Iranian Journal of Science and Technology, Transaction A. 29, 357–366(2005).
  • NajaŞ, B., Tayebi, A., Rezaei, M. M.: General relatively isotropic mean Landsberg Finsler manifolds, Iranian Journal of Science and Technology, Transaction A. 29, 497–505 (2005).
  • Randers, G.: On an asymmetric metric in the four-space of general relativity, Phys. Rev. 59, 195–199 (1941).
  • Shen, Z.: Differential Geometry of Spray and Finsler Spaces, Kluwer Academic Publishers, 2001.
  • Tayebi, A., Azizpour, E., EsraŞlian, E.: On a family of connections in Finsler geometry, Publ. Math. Debrecen. , 1–15 (2008).
  • Tayebi, A., NajaŞ, B.: Shen’s processes on Finslerian connection, Bull. Iran. Math. Soc. 36, No. 2, 57–73 (2010).
  • Tayebi, A., Peyghan, E.: On special Berwald metrics, Symmetry, Integrability and Geometry: Methods and its Applications, 6 (2010), 008, 9 page.
  • Tayebi, A., RaŞe. Rad, M.: S-curvature of isotropic Berwald metrics, Science in China, Series A: Mathematics. , 2198–2204 (2008). Esmaeil PEYGHAN
  • Department of Mathematics, Faculty of Science Arak University, Arak, 38156-8-8349, IRAN e-mail: epeyghan@gmail.com Akbar TAYEBI
  • Department of Mathematics, Faculty of Science Qom University, Qom-IRAN e-mail: akbar.tayebi@gmail.com