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相关论文: On the Pontrjagin classes of spray manifolds

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The projective Finsler metrizability problem deals with the question whether a projective-equivalence class of sprays is the geodesic class of a (locally or globally defined) Finsler function. In this paper we use Hilbert-type forms to…

微分几何 · 数学 2013-01-14 M. Crampin , T. Mestdag , D. J. Saunders

Geodesics, which play an important role in spray-Finsler geometry, are integral curves of a spray vector field on a manifold. Some comparison theorems and rigidity issues are established on the completeness of geodesics of a spray or a…

微分几何 · 数学 2023-01-03 Guojun Yang

The projective metrizability problem can be formulated as follows: under what conditions the geodesics of a given spray coincide with the geodesics of some Finsler space, as oriented curves. In Theorem 3.8 we reformulate the projective…

微分几何 · 数学 2011-12-13 Ioan Bucataru , Zoltán Muzsnay

The well-known Funk metric F(x,y) is projectively flat with constant flag curvature K=-1/4 and the Hilbert metric H(x,y):=(F(x,y)+F(x,-y))/2 is projectively flat with constant curvature K=-1. These metrics are the special solutions to…

微分几何 · 数学 2007-05-23 Zhongmin Shen

In this paper, we introduce the notion of one form deformation of sprays. The metrizability of the new spray, when the background spray is flat, is characterized. Therefore, we obtain new projectively flat metrics of constant flag curvature…

微分几何 · 数学 2018-07-06 S. G. Elgendi

In this work we show that for the geodesic spray $S$ of a Finsler function $F$ the most natural projective deformation $\widetilde{S}=S -2 \lambda F\mathbb C$ leads to a non-Finsler metrizable spray, for almost every value of $\lambda \in…

微分几何 · 数学 2012-08-02 Ioan Bucataru , Zoltán Muzsnay

This paper studies spherically symmetric sprays, i.e., sprays that are invariant under orthogonal transformations. We first establish a canonical form for such sprays, showing that their geodesic coefficients can be expressed as \(G^i =…

微分几何 · 数学 2026-04-15 Yajing Gui , Benling Li

In the previous work, the notion of the Finsleroid--Finsler space have been formulated and the necessary and sufficient conditions for the space to be of the Landsberg type have been found. In the present paper, starting with particular…

微分几何 · 数学 2007-05-23 G. S. Asanov

This paper is concerned with the problem of determining whether a projective-equivalence class of sprays is the geodesic class of a Finsler function. We address both the local and the global aspects of this problem. We present our results…

微分几何 · 数学 2012-10-19 M. Crampin , T. Mestdag , D. J. Saunders

Every Finsler metric naturally induces a spray but not so for the converse. The notion for sprays of scalar (resp. isotropic) curvature has been known as a generalization for Finsler metrics of scalar (resp. isotropic) flag curvature. In…

微分几何 · 数学 2022-05-25 Guojun Yang

In this paper we study the invariant metrizability and projective metrizability problems for the special case of the geodesic spray associated to the canonical connection of a Lie group. We prove that such canonical spray is projectively…

微分几何 · 数学 2016-10-28 Ioan Bucataru , Tamás Milkovszki , Zoltán Muzsnay

In 2001, Zhongmin Shen asked if it is possible for two projectively related Finsler metrics to have the same Riemann curvature tensor, [14, page 184]. In this paper, we provide an answer to this question, within the class of Finsler metrics…

微分几何 · 数学 2016-09-12 Ioan Bucataru

In this paper we study a class of Finsler metrics defined by a Riemannian metric and an 1-form. We classify those of projectively flat in dimension $n\geq3$ by a special class of deformations. The results show that the projective flatness…

微分几何 · 数学 2013-05-17 Changtao Yu

Based on a self-contained, coordinate-free exposition of the necessary concepts and tools of spray and Finsler geometry (with detailed proofs), we derive new results among others on the consequences of the direction-independence of the…

微分几何 · 数学 2010-01-26 Zoltán Szilasi

In this paper, we study a class of Finsler metrics composed by a Riemann metric $\alpha=\sqrt{a_{ij}(x)y^i y^j}$ and a $1$-form $\beta=b_i(x)y^i$ called general ($\alpha$, $\beta$)-metrics. We classify those projectively flat when $\alpha$…

微分几何 · 数学 2015-10-22 Benling Li , Zhongmin Shen

In this paper we characterize sprays that are metrizable by Finsler functions of constant flag curvature. By solving a particular case of the Finsler metrizability problem we provide the necessary and sufficient conditions that can be used…

微分几何 · 数学 2013-04-23 Ioan Bucataru , Zoltán Muzsnay

It is well known that a system of homogeneous second-order ordinary differential equations (spray) is necessarily isotropic in order to be metrizable by a Finsler function of scalar flag curvature. In Theorem 3.1 we show that the isotropy…

微分几何 · 数学 2014-07-25 Ioan Bucataru , Zoltán Muzsnay

The class of spherically symmetric Finsler metrics is studied and locally dually flat and projectively flat spherically symmetric Finsler metrics is classified.

微分几何 · 数学 2015-03-19 Behzad Najafi

For a Finsler metric $F$, we introduce the notion of $F$-covariant coefficients $H_i$ of the geodesic spray of $F$ (Def. 3.1). We study some geometric consequences concerning the objects $H_i$. If the $F$-covariant coefficients $H_i$ are…

微分几何 · 数学 2025-01-06 S. G. Elgendi , A. Soleiman , Nabil L. Youssef

We define a partition of the space of projectively flat metrics in three classes according to the sign of the Chern scalar curvature; we prove that the class of negative projectively flat metrics is empty, and that the class of positive…

微分几何 · 数学 2021-03-25 Simone Calamai
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