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Related papers: Quasi-Topological Ricci Polynomial Gravities

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We study the non-relativistic (NR) limit of relativistic spacetimes in relation with the topology of the Universe. We first show that the NR limit of the Einstein equation is only possible in Euclidean topologies, i.e. for which the…

General Relativity and Quantum Cosmology · Physics 2024-01-09 Quentin Vigneron

The general relativity theory is redefined equivalently in almost Kahler variables: symplectic form and canonical symplectic connection (distorted from the Levi-Civita connection by a tensor constructed only from metric coefficients and…

Mathematical Physics · Physics 2009-11-21 Sergiu I. Vacaru

We extend Maldacena's argument, namely, obtaining Einstein gravity from Conformal Gravity, to six dimensional manifolds. The proof relies on a particular combination of conformal (and topological) invariants, which makes manifest the fact…

High Energy Physics - Theory · Physics 2021-02-24 Giorgos Anastasiou , Ignacio J. Araya , Rodrigo Olea

In this thesis, we focus on higher-curvature extensions of Einstein gravity as toy models to probe universal properties of conformal field theory (CFT) using the gauge/gravity duality. In this context, we are particularly interested in…

High Energy Physics - Theory · Physics 2022-07-27 Javier Moreno

We construct solutions of higher-dimensional Einstein gravity coupled to nonlinear $\sigma$-model with cosmological constant. The $\sigma$-model can be perceived as exterior configuration of a spontaneously-broken $SO(D-1)$ global…

General Relativity and Quantum Cosmology · Physics 2017-08-30 Ilham Prasetyo , Handhika S. Ramadhan

We model pseudo-Finsler geometries, with pseudo-Euclidean signatures of metrics, for two classes of four dimensional nonholonomic manifolds: a) tangent bundles with two dimensional base manifolds and b) pseudo-Riemannian/ Einstein…

General Relativity and Quantum Cosmology · Physics 2013-04-09 Sergiu I. Vacaru

In this work we construct and analyze exact solutions describing Ricci flows and nonholonomic deformations of four dimensional (4D) Taub-NUT spacetimes. It is outlined a new geometric techniques of constructing Ricci flow solutions. Some…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergiu I. Vacaru , Mihai Visinescu

This paper studies a class of $D=n+2(\ge 6)$ dimensional solutions to Lovelock gravity that is described by the warped product of a two-dimensional Lorentzian metric and an $n$-dimensional Einstein space. Assuming that the angular part of…

General Relativity and Quantum Cosmology · Physics 2015-10-27 Seiju Ohashi , Masato Nozawa

We consider a theory of gravity with a hidden extra-dimension and metric-dependent torsion. A set of physically motivated constraints are imposed on the geometry so that the torsion stays confined to the extra-dimension and the…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Karthik H. Shankar , Anand Balaraman , Kameshwar C. Wali

In the background of unparticle-enhanced black hole geometry, we provide the quasinormal modes of scalar, vector, and Dirac particles around it. Ungravity by tensor unparticles contributes positively to the Newtonian gravity and black holes…

High Energy Physics - Phenomenology · Physics 2015-05-28 Jong-Phil Lee

We construct an n-dimensional Born-Infeld type gravity theory that has the same properties as Einstein's gravity in terms of the vacuum and particle content: Namely, the theory has a unique viable vacuum (maximally symmetric solution) and a…

High Energy Physics - Theory · Physics 2015-11-11 Ibrahim Gullu , Tahsin Cagri Sisman , Bayram Tekin

A generalization of Ricci-like solitons with torse-forming potential, which is a constant multiple of the Reeb vector field, is studied. The conditions under which these solitons are equivalent to almost Einstein-like metrics are given.…

Differential Geometry · Mathematics 2021-06-22 Mancho Manev

We present a topological classification of vacuum space-time. Assuming the 3-dimensional space allows a global chart, we show that the static vacuum space-time of Einstein's theory can be classified by the knot topology…

High Energy Physics - Theory · Physics 2007-05-23 Y. M. Cho

I consider theories of gravity built not just from the metric and affine connection, but also other (possibly higher rank) symmetric tensor(s). The Lagrangian densities are scalars built from them, and the volume forms are related to…

High Energy Physics - Theory · Physics 2020-04-06 Chethan Krishnan

We construct Einstein metrics of non-positive scalar curvature on certain solid torus bundles over a Fano Kahler-Einstein manifold. We show, among other things, that the negative Einstein metrics are conformally compact, and the Ricci-flat…

Differential Geometry · Mathematics 2011-03-07 Dezhong Chen

Based on a well-known fact that there are no Einstein hypersurfaces in a non-flat complex space form, in this article we study the quasi-Einstein condition, which is a generalization of an Einstein metric, on the real hyersurface of a…

Differential Geometry · Mathematics 2019-09-04 Xiaomin Chen

We derive the general $\Sigma_2\times S$ solution of topologically massive gravity in vacuum and in presence of a cosmological constant. The field equations reduce to three-dimensional Einstein equations and the solution has constant Ricci…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marco Cavaglia

In the paper, we study complete almost Ricci solitons using the concepts and methods of geometric dynamics and geometric analysis. In particular, we characterize Einstein manifolds in the class of complete almost Ricci solitons. Then, we…

Differential Geometry · Mathematics 2023-04-10 Vladimir Rovenski , Sergey Stepanov , Irina Tsyganok

General Einstein-Gauss-Bonnet gravity with a cosmological constant allows two (A)dS spacetimes as its vacuum solutions. We find a critical point in the parameter space where the two (A)dS spacetimes coalesce into one and the linearized…

High Energy Physics - Theory · Physics 2016-11-03 Zhong-Ying Fan , Bin Chen , Hong Lu

I propose an alternative $f(R)$ theory of gravity constructed by applying the function $f$ directly to the Ricci tensor instead of the Ricci scalar. The main goal of this study is to derive the resulting modified Einstein equations for the…

General Relativity and Quantum Cosmology · Physics 2017-08-16 Tomasz Stachowiak
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