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Related papers: Some remarks on Einstein-Randers metrics

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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

There are described hierarchies of equations coupling a metric with a trace-free tensor having prescribed symmetries and in the kernel of certain generalized gradients. These specialize, when the tensor vanishes identically, to the usual…

Differential Geometry · Mathematics 2025-02-12 Daniel J. F. Fox

We describe and construct here pseudo-Hermitian structures $\theta$ without torsion (i.e. with transversal symmetry) whose Webster-Ricci curvature tensor is a constant multiple of the exterior differential $d\theta$. We call these…

Differential Geometry · Mathematics 2007-05-23 Felipe Leitner

In the present paper, the notion of $\mathbb{R}$-complex Finsler space with Infinite Series ($\alpha, \beta$)- metric $\dfrac{\beta^2}{\beta - \alpha}$ is defined. The Fundamental metric fields $g_{ij}$, $g_{i\bar{j}}$, their determinants…

Differential Geometry · Mathematics 2018-03-06 Gauree Shanker , Ruchi Kaushik Sharma

We classify the Ricci flat Lorentzian $n$-manifolds satisfying three particular conditions, encoding and combining some crucial features of the Kerr metrics and the Robinson-Trautman optical structures. We prove that: (a) If $n>4$, there is…

Differential Geometry · Mathematics 2025-01-14 Masoud Ganji , Cristina Giannotti , Gerd Schmalz , Andrea Spiro

A new geometrical definition of naturally reductive Finsler manifold using geodeic graph is proposed, with a possible generalization. Based on a construction from a recent paper by the authors, Finsler metrics based on naturally reductive…

Differential Geometry · Mathematics 2025-10-28 Teresa Arias-Marco , Zdenek Dusek

We derive new, sharp lower bounds for certain curvature functionals on the space of Riemannian metrics of a smooth compact 4-manifold with a non-trivial Seiberg-Witten invariant. These allow one, for example, to exactly compute the infimum…

Differential Geometry · Mathematics 2009-10-31 Claude LeBrun

This paper is concerned with the construction of special metrics on non-compact 4-manifolds which arise as resolutions of complex orbifold singularities. Our study is close in spirit to the construction of the hyperkaehler gravitational…

Differential Geometry · Mathematics 2015-06-26 David M. J. Calderbank , Michael A. Singer

Lorentz Invariance violation is a common feature of new physics beyond the standard model. We show that the symmetry of Randers spaces deduces a modified dispersion relation with characteristics of Lorentz Invariance violation. The…

High Energy Physics - Theory · Physics 2008-04-07 Zhe Chang , Xin Li

Recently the neglected issue of the causal structure in the flat spacetime approach to Einstein's theory of gravity has been substantially resolved. Consistency requires that the flat metric's null cone be respected by the null cone of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Brian Pitts , W. C. Schieve

In this paper, we study regular sets in metric measure spaces with bounded Ricci curvature. We prove that the existence of a point in the regular set of the highest dimension implies the positivity of the measure of such regular set. Also…

Metric Geometry · Mathematics 2017-08-16 Yu Kitabeppu

We give the explicit formulas of the flag curvatures of left invariant Matsumoto and Kropina metrics of Berwald type. We can see these formulas are different from previous results given recently. Using these formulas, we prove that at any…

Differential Geometry · Mathematics 2024-07-23 Masoumeh Hosseini , Hamid Reza Salimi Moghaddam

We find all orthogonal metrics where the geodesic Hamilton-Jacobi equation separates and the Riemann curvature tensor satisfies a certain equation (called the diagonal curvature condition). All orthogonal metrics of constant curvature…

Mathematical Physics · Physics 2015-06-19 Krishan Rajaratnam , Raymond G. McLenaghan

We propose a sufficient condition for a general spherical symmetric static metric to be compatible with classical tests of gravity. A 1-parametric class of such metrics are constructed. The Schwarzschild metric as well as the Yilmaz-Rosen…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yakov Itin

The difference tensor C.R - R.C of Einstein manifolds, some quasi-Einstein manifolds and Roter type manifolds, of dimension n > 3, satisfy the following curvature condition: (A) C.R - R.C = Q(S,C) - (k /(n-1)) Q(g,C). We investigate…

Differential Geometry · Mathematics 2019-03-06 Ryszard Deszcz , Malgorzata Glogowska , Georges Zafindratafa

Finsler geometry is a natural arena to investigate the physics of spacetimes with local Lorentz violating. The directional dependence of the Finsler metric provides a way to encode the Lorentz violating effects into the geometric structure…

High Energy Physics - Theory · Physics 2021-04-29 J. E. G. Silva

Spacelike intrinsic rotational surfaces with constant mean curvature in the Lorentz-Minkowski space $\E_1^3$ have been recently investigated by Brander et al., extending the known Smyth's surfaces in Euclidean space. Assuming that the…

Differential Geometry · Mathematics 2024-12-02 Seher Kaya , Rafael López

We develop the theory of left-invariant generalized pseudo-Riemannian metrics on Lie groups. Such a metric accompanied by a choice of left-invariant divergence operator gives rise to a Ricci curvature tensor and we study the corresponding…

Differential Geometry · Mathematics 2023-02-22 Vicente Cortés , David Krusche

We classify solutions to Einstein's equations in AdS with Ricci-flat boundary metric and with covariantly constant boundary stress tensor, which in general is not diagonalizable, i.e. it does not admit a reference frame. New solutions are…

General Relativity and Quantum Cosmology · Physics 2017-01-30 Paolo Glorioso

The effect of curvature on the results of fractal analyses of the galaxy distribution is investigated. We show that, if the universe satisfies the criteria of a wide class of parabolic homogeneous models, the observers measuring the fractal…

Astrophysics · Physics 2009-10-31 Marie-Noëlle Célérier , Reuben Thieberger