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Related papers: Nonsingular Universes in Gauss-Bonnet Gravity's Ra…

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One of the fundamental open questions in cosmology is whether we can regard the universe evolution without singularity like a Big Bang or a Big Rip. This challenging subject stimulates one to regard a nonsingular universe in the far past…

General Relativity and Quantum Cosmology · Physics 2022-08-09 Seyed Hossein Hendi , Mehrab Momennia , Behzad Eslam Panah , Shahram Panahiyan

In this work, we study FRW cosmologies in the context of gravity rainbow. We discuss the general conditions for having a nonsingular FRW cosmology in gravity rainbow. We propose that gravity rainbow functions can be fixed using two known…

General Relativity and Quantum Cosmology · Physics 2013-11-15 Adel Awad , Ahmed Farag Ali , Barun Majumder

The formalism of rainbow gravity is studied in a cosmological setting. We consider the very early universe which is radiation dominated. A novel treatment in our paper is to look for an ``averaged'' cosmological metric probed by radiation…

General Relativity and Quantum Cosmology · Physics 2009-07-07 Yi Ling

We investigate the constraints imposed by the Weak Gravity Conjecture (WGC) on gravitational lensing in gravity's rainbow, focusing in particular on scenarios beyond extremality and on the interplay between the WGC and the Weak Cosmic…

General Relativity and Quantum Cosmology · Physics 2025-12-10 Saeed Noori Gashti , Behnam Pourhassan , Izzet Sakallı

By presenting a relation between average energy of the ensemble of probe photons and energy density of the Universe, in the context of {\it gravity's rainbow} or {\it doubly general relativity} scenario, we introduce a rainbow FRW Universe…

General Relativity and Quantum Cosmology · Physics 2015-12-15 M. Khodadi , Y. Heydarzade , K. Nozari , F. Darabi

The usual Einstein's equations is modified as a one parameter family of equations in the framework of rainbow gravity. In this paper we derive the modified Friedmann-Robertson-Walker (FRW) equations when the cosmological evolution of…

General Relativity and Quantum Cosmology · Physics 2010-04-15 Yi Ling , Qingzhang Wu

Occurrence of spacetime singularities is one of the peculiar features of Einstein gravity, signalling limitation on probing short distances in spacetime. This alludes to the existence of a fundamental length scale in nature. On contrary,…

General Relativity and Quantum Cosmology · Physics 2020-12-21 Omar El-Refy , Syed Masood , Li-Gang Wang , Ahmed Farag Ali

Isotropic quantum cosmological perfect fluid model is studied in the formalism of Rainbow gravity. It is found that the only surviving matter degree of freedom played the role of cosmic time. It is possible to find the wave packet naturally…

General Relativity and Quantum Cosmology · Physics 2013-09-26 Barun Majumder

We investigate FRW cosmological solutions in the theory of modulus field coupled to gravity through a Gauss-Bonnet term. The explicit analytical forms of nonsingular asymptotics are presented for power-law and exponentially steep modulus…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. O. Alexeyev , A. V. Toporensky , V. O. Ustiansky

In this article, we examine the possibility that there exist special scalar-tensor theories of gravity with completely nonsingular FRW solutions. Our investigation in fact shows that while most probes living in such a Universe never see the…

High Energy Physics - Theory · Physics 2009-09-15 Nemanja Kaloper , Keith A. Olive

The modified Gauss-Bonnet gravity can be motivated by a number of physical reasons, including: the uniqueness of a gravitational Lagrangian in four and higher dimensions and the leading order $\alpha^\prime$ corrections in superstring…

High Energy Physics - Theory · Physics 2017-08-23 Ishwaree P. Neupane

Six-dimensional Einstein-Gauss-Bonnet gravity (with a linear Gauss-Bonnet term) is investigated. This theory is inspired by basic features of results coming from string and M-theory. Dynamical compactification is carried out and it is seen…

High Energy Physics - Theory · Physics 2008-11-26 E. Elizalde , A. N. Makarenko , V. V. Obukhov , K. E. Osetrin , A. E. Filippov

Infinite Derivative Gravity is able to resolve the Big Bang curvature singularity present in general relativity by using a simplifying ansatz. We show that it can also avoid the Hawking- Penrose singularity, by allowing defocusing of null…

General Relativity and Quantum Cosmology · Physics 2018-08-13 James Edholm

We investigate the future evolution of the dark energy universe in modified gravities including $F(R)$ gravity, string-inspired scalar-Gauss-Bonnet and modified Gauss-Bonnet ones, and ideal fluid with the inhomogeneous equation of state…

High Energy Physics - Theory · Physics 2009-09-17 Kazuharu Bamba , Shin'ichi Nojiri , Sergei D. Odintsov

We investigate the gravitational baryogenesis scenario within the context of $F(R)$ gravity's rainbow which incorporates both modified gravity and energy-dependent spacetime. This study explores a mechanism for generating baryon asymmetry…

General Relativity and Quantum Cosmology · Physics 2026-02-09 Parviz Goodarzi

In this paper, we will generalize the Gauss-Bonnet gravity to an energy dependent Gauss-Bonnet theory of gravity, which we shall call as the Gauss-Bonnet gravity's rainbow. We will also couple this theory to a Maxwell's theory. We will…

General Relativity and Quantum Cosmology · Physics 2015-08-26 Seyed Hossein Hendi , Mir Faizal

We provide a rigorous proof for the existence of homogeneous, isotropic and globally singularity-free cosmological solutions in Einstein-dilaton-Gauss-Bonnet (EdGB) gravity with exponential coupling. While numerical studies suggested such…

Analysis of PDEs · Mathematics 2025-12-02 Chihang He , Chao Liu

Rainbow gravity modifies general relativity by introducing an energy dependent metric, which is expected to have a role in the quantum theory of black holes and in quantum gravity at Planck energy scale. We show that rainbow gravity can be…

General Relativity and Quantum Cosmology · Physics 2018-06-07 Maria Chiara Braidotti , Claudio Conti

The concept of smooth deformations of a Riemannian manifolds, recently evidenced by the solution of the Poincar\'e conjecture, is applied to Einstein's gravitational theory and in particular to the standard FLRW cosmology. We present a…

General Relativity and Quantum Cosmology · Physics 2015-03-17 M. D. Maia , A. J. S. Capistrano , J. S. Alcaniz , Edmundo M. Monte

We compute the Zero Point Energy in a spherically symmetric background combining the high energy distortion of Gravity's Rainbow with the modification induced by a f(R) theory. Here f(R) is a generic analytic function of the Ricci curvature…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Remo Garattini
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