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Related papers: Finsler surfaces with vanishing $T$-tensor

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This study presents many special anisotropic conformal changes of a conic pseudo-Finsler surface $(M,F)$, such as $C$-anisotropic and horizontal $C$-anisotropic conformal transformations, which reduce to $C$-conformal when the conformal…

Differential Geometry · Mathematics 2025-05-29 Nabil L. Youssef , Ebtsam H. Taha , A. A. Kotb , S. G. Elgendi

We describe the $(\alpha,\beta)$-metrics whose the $T$-tensor vanishes ($T$-condition) and the $(\alpha,\beta)$-metrics that satisfy the $\sigma T$-condition $\sigma_hT^h_{ijk}=0$, where $\sigma_h=\frac{\partial \sigma}{\partial x^h}$ and…

Differential Geometry · Mathematics 2021-10-15 S. G. Elgendi , Laszlo Kozma

In this paper, we study the long existence problem of non Berwaldian Landsberg spaces using the conformal transformation point of view. Under conformal transformation, the Berwald and Landesberg tensors are calculated in terms of the…

Differential Geometry · Mathematics 2018-01-29 S. G. Elgendi

This paper is a continuation of our investigation of the anisotropic conformal change of a conic pseudo-Finsler surface $(M,F)$, namely, the change $\overline{F}(x,y)=e^{\phi(x,y)}F(x,y)$ \cite{first paper}. We obtain the relationship…

Differential Geometry · Mathematics 2025-03-12 Nabil L. Youssef , S. G. Elgendi , A. A. Kotb , Ebtsam H. Taha

In this paper, we introduce a new look at Finsler surfaces. Landsberg surfaces are Finsler surfaces that are solutions of a system of non-linear partial differential equations. Considering the unicorn's Landsberg problem, we reduce this…

Differential Geometry · Mathematics 2022-08-09 Salah G. Elgendi

In this paper, as an application of the inverse problem of calculus of variations, we investigate two compatibility conditions on the spherically symmetric Finsler metrics. By making use of these conditions, we focus our attention on the…

Differential Geometry · Mathematics 2021-10-15 S. G. Elgendi

In the present paper, we find out necessary and sufficient conditions for a Finsler surface $(M,F)$ to be Landsbregian in terms of the Berwald curvature $2$-forms. We study Finsler surfaces which satisfy some flag curvature $K$ conditions,…

Differential Geometry · Mathematics 2022-09-16 Ebtsam H. Taha

By performing required evaluations, we show that in the Finsleroid-regular space the Landsberg-space condition just degenerates to the Berwald-space condition (at any dimension number $N\ge2$). Simple and clear expository representations…

Differential Geometry · Mathematics 2008-01-31 G. S. Asanov

In this paper, we investigate the change of Finslr metrics $$L(x,y) \to\bar{L}(x,y) = f(e^{\sigma(x)}L(x,y),\beta(x,y)),$$ which we refer to as a generalized $\beta$-conformal change. Under this change, we study some special Finsler spaces,…

Differential Geometry · Mathematics 2015-03-17 Nabil L. Youssef , S. H. Abed , S. G. Elgendi

Berwald geometries are Finsler geometries close to (pseudo)-Riemannian geometries. We establish a simple first order partial differential equation as necessary and sufficient condition, which a given Finsler Lagrangian has to satisfy to be…

Differential Geometry · Mathematics 2021-10-12 Christian Pfeifer , Sjors Heefer , Andrea Fuster

In this paper, we prove that all spherically symmetric Landsberg surfaces are Berwaldian. We modify the classification of spherically symmetric Finsler metrics, done by the author in [S. G. Elgendi, On the classification of Landsberg…

Differential Geometry · Mathematics 2023-02-21 Salah G. Elgendi

Finsler metrics are direct generalizations of Riemannian metrics such that the quadratic Riemannian indicatrices in the tangent spaces of a manifold are replaced by more general convex bodies as unit spheres. A linear connection on the base…

Differential Geometry · Mathematics 2022-04-05 Csaba Vincze , Márk Oláh

On a Finsler manifold $(M,L)$, we consider the change $L\longrightarrow\bar{L}(x,y)=e^{\sigma(x)}L(x,y)+\beta (x,y)$, which we call a $\beta$-conformal change. This change generalizes various types of changes in Finsler geometry: conformal,…

Differential Geometry · Mathematics 2007-06-13 S. H. Abed

The problem of conformal transformation and conformal flatness of Finsler spaces has been studied by so many researchers $\left[ 6,16,17,20,21\right] .$ Recently, Prasad et. al $\left[ 19\right] $ have studied three dimensional conformally…

Differential Geometry · Mathematics 2017-12-21 Gauree Shanker

In this short note, we verify R. Bryant's claim: there does exist the singular Landsberg Finsler surface with a vanishing flag curvature which is not Berwaldian.

Differential Geometry · Mathematics 2012-09-26 Linfeng Zhou

This paper is devoted to the study of the T-tensor associated with a spherically symmetric Finsler metric $F=u\phi(r,s)$ on \(\mathbb{R}^n\). We derive a general expression for the T-tensor in terms of the scalar function \(\phi(r, s)\) and…

Differential Geometry · Mathematics 2026-01-23 Salah G. Elgendi

We show that which that for a Berwald structure, any Riemannian structure that is preserved by the Berwald connection leaves the indicatrix invariant under horizontal parallel transport. We also obtain the converse result: if $({\bf M},F)$…

Differential Geometry · Mathematics 2020-03-13 Ricardo Gallego Torrome , Fernando Etayo

We investigate what we call a conformal $\beta $ - change in Finsler spaces, namely $$ L(x,y)\to ~^{\ast}L(x,y)=e^{\sigma(x)}L(x,y)+\beta(x,y)$$ where~$\sigma ~$ is a function of $x~ only ~and ~ \beta (x, y)$ is a given 1- form. This change…

Differential Geometry · Mathematics 2007-05-23 S. H. Abed

For the general class of pseudo-Finsler spaces with $(\alpha,\beta)$-metrics, we establish necessary and sufficient conditions such that these admit a Finsler spacetime structure. This means that the fundamental tensor has Lorentzian…

Differential Geometry · Mathematics 2023-09-12 Nicoleta Voicu , Annamária Friedl-Szász , Elena Popovici-Popescu , Christian Pfeifer

We formulate the notion of the Finsleroid--Finsler space, including the positive--definite as well as indefinite cases. The associated concepts of angle, scalar product, and the distance function are elucidated. If the Finsleroid--Finsler…

Differential Geometry · Mathematics 2007-05-23 G. S. Asanov
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