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In this work, we apply quantum corrected entropy function derived from the Generalized Uncertainty Principle (GUP) to the Holographic Equipartition Law to study the cosmological scenario in Randall-Sundrum (RS) II brane. An extra driving…

General Relativity and Quantum Cosmology · Physics 2018-11-05 Tanwi Bandyopadhyay

We investigate a $(n+1)$-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale factors. One obtain a positive effective cosmological constant $\Omega_{eff}\sim10^{-124}$ (in Planck unit)…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Guang-Zhen Kang , De-Sheng Zhang , Long Du , Dan Shan , Hong-Shi Zong

We propose a phenomenological approach to the cosmological constant problem based on generally covariant non-local and acausal modifications of four-dimensional gravity at enormous distances. The effective Newton constant becomes very small…

High Energy Physics - Theory · Physics 2007-05-23 Nima Arkani-Hamed , Savas Dimopoulos , Gia Dvali , Gregory Gabadadze

It is shown that Einstein field equations give two solutions for cosmology. The first one is the standard well known representative of the present status of cosmology. We identify it with the local point of view of a flat Universe with the…

General Physics · Physics 2008-01-04 Antonio Alfonso-Faus

Numerical evidence for a cosmological version of the Bartnik-McKinnon family of particle-like solutions of the Einstein-Yang-Mills system is presented. Our solutions are also static, but space has the topology of a three-sphere. By…

General Relativity and Quantum Cosmology · Physics 2008-02-03 P. Molnar

Cosmography is a useful tool to constrain cosmological models, in particular dark energy models. In the case of modified theories of gravity, where the equations of motion are generally quite complicated, cosmography can contribute to…

General Relativity and Quantum Cosmology · Physics 2010-12-23 Mariam Bouhmadi-Lopez , Salvatore Capozziello , Vincenzo F. Cardone

A framework is introduced which explains the existence and similarities of most exact solutions of the Einstein equations with a wide range of sources for the class of hypersurface-homogeneous spacetimes which admit a Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Claes Uggla , Robert T. Jantzen , Kjell Rosquist

We study an analytical solution to the Einstein's equations in 2+1-dimensions. The space-time is dynamical and has a line symmetry. The matter content is a minimally coupled, massless, scalar field. Depending on the value of certain…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. Oliveira-Neto

We approach the cosmological inflation thought symmetries of differential equations. We consider the general inflaton field in a homogeneous Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime and with the use of conformal transformations…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Andronikos Paliathanasis

We construct an asymptotic series for a general solution of the Einstein equations near a sudden singularity. The solution is quasi isotropic and contains nine independent arbitrary functions of the space coordinates as required by the…

General Relativity and Quantum Cosmology · Physics 2010-07-29 J. D. Barrow , S. Cotsakis , A. Tsokaros

We study the evolution of the metric perturbations in a Bianchi background in the long-wavelength limit. By applying the gradient expansion to the equations of motion we exhibit a generalized "Separate Universe" approach to the cosmological…

General Relativity and Quantum Cosmology · Physics 2018-03-13 Alireza Talebian-Ashkezari , Nahid Ahmadi , Ali Akbar Abolhasani

Modifying the standard hot big bang model of cosmology with an inflationary event has been very successful in resolving most of the outstanding cosmological problems. The various inflationary mechanisms proposed depend on the production of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Akinbo Ojo

A companion paper provides a proposal for cosmic singularity resolution based upon general features of a bouncing unitary cosmological model in the mini-superspace approximation. This paper analyses novel phenomenology that can be…

General Relativity and Quantum Cosmology · Physics 2018-12-17 Sean Gryb , Karim P. Y. Thébault

In a series of articles we describe a novel class of geometrical models of relativistic stars. Our approach to the static spherically symmetric solutions of Einstein equations is based on a careful physical analysis of radial gauge…

Astrophysics · Physics 2007-05-23 P. P. Fiziev

We use cosmography to present constraints on the kinematics of the Universe without postulating any underlying theoretical model a priori. To this end, we use a Markov Chain Monte Carlo analysis to perform comparisons to the supernova Ia…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo

The theory of cosmic inflation has received a great amount of deserved attention in recent years due to it's stunning predictions about the early universe. Alongside the usual cold inflation paradigm, warm inflation has garnered a huge…

General Relativity and Quantum Cosmology · Physics 2024-08-02 Oem Trivedi

A static Friedmann brane in a 5-dimensional bulk (Randall-Sundrum type scenario) can have a very different relation between the density, pressure, curvature and cosmological constant than in the case of the general relativistic Einstein…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Laszlo Gergely , Roy Maartens

We briefly discuss new models of an `affine' theory of gravity in multidimensional space-times with symmetric connections. We use and generalize Einstein's proposal to specify the space-time geometry by use of the Hamilton principle to…

General Relativity and Quantum Cosmology · Physics 2017-08-23 A. T. Filippov

We discuss the possibility that the inflationary paradigm, undoubtfully today's best framework to understand all the present cosmological data, may still have some viable challengers. The underlying idea for such discussions is that…

General Relativity and Quantum Cosmology · Physics 2010-11-15 P. Peter

We provide a new extension of general relativity (GR) which has the remarkable property of being more constrained than GR plus a cosmological constant, having one less free parameter. This is implemented by allowing the cosmological…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Stephon Alexander , Marina Cortês , Andrew R. Liddle , João Magueijo , Robert Sims , Lee Smolin