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Related papers: Generalizing the Cosmic Energy Equation

200 papers

We develop a new model for the Universe based on two key assumptions: first, the inertial energy of the Universe is a constant, and second, the total energy of a particle, the inertial plus the gravitational potential energy produced by the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hossein Shojaie , Mehrdad Farhoudi

High-precision observational data have confirmed with startling evidence that the Universe is currently undergoing a phase of accelerated expansion. This phase, one of the most important and challenging current problems in cosmology,…

General Relativity and Quantum Cosmology · Physics 2015-08-20 Sebastian Bahamonde , Christian G. Boehmer , Francisco S. N. Lobo , Diego Saez-Gomez

We examine the possibility that a significant component of the energy density of the universe has an equation-of-state different from that of matter, radiation or cosmological constant ($\Lambda$). An example is a cosmic scalar field…

Astrophysics · Physics 2009-09-15 R. R. Caldwell , Rahul Dave , Paul J. Steinhardt

We consider a simplified model of quantum gravity using a mini-superspace description of an isotropic and homogeneous universe with dust. We derive the corresponding Friedmann equations for the scale factor, which now contain a dependence…

General Relativity and Quantum Cosmology · Physics 2020-04-03 Thibaut Demaerel , Christian Maes , Ward Struyve

The backreaction of structure formation influences the cosmological evolution equation for the homogenous and isotropic average metric. In a cold dark matter universe this effect leads only to small corrections unless a substantial fraction…

Astrophysics · Physics 2009-11-07 C. Wetterich

We suggest that using the first law of thermodynamics is a convenient method to obtain a correct form of the expansion law of the universe \cite{T. Padmanabhan1}. We will, then, use this idea to obtain the expansion law for a Kodama…

General Relativity and Quantum Cosmology · Physics 2015-07-07 Fatemeh Lalehgani Dezaki , Behrouz Mirza

There is now strong observational evidence that the expansion of the universe is accelerating. The standard explanation invokes an unknown "dark energy" component. But such scenarios are faced with serious theoretical problems, which has…

Astrophysics · Physics 2008-11-26 Martin Kunz , Domenico Sapone

H.A. Wilson, then R.H. Dicke, proposed to describe gravitation by a spatial change of the refractive index of the vacuum around a gravitational mass. Dicke extended this formalism in order to describe the apparent expansion of the Universe…

General Physics · Physics 2018-06-06 X. Sarazin , F. Couchot , A. Djannati-Atai , M. Urban

Based on Wheeler-DeWitt equation derived from general relativity, it had been found that only dark energy can lead to a normalizable cosmological wave function. It is shown in the present work that, for dRGT gravity,…

General Relativity and Quantum Cosmology · Physics 2017-05-09 Peng Huang , Yue Huang

The Einstein equation in a semi-classical approximation is applied to a spherical region of the universe, with the stress-energy tensor consisting of the mass density and pressure of the LambdaCDM cosmological model plus an additional…

General Relativity and Quantum Cosmology · Physics 2024-12-11 Emilio Santos

We consider the generalized particle dynamics, proposed by us, in brane world formalisms for an asymptotically anti de Sitter background. The present framework results in a new model that accounts for the late acceleration of the universe.…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-25 Sudipta Das , Subir Ghosh , Jan-Willem van Holten , Supratik Pal

Through averaging the Einstein equations over transverse gravitational perturbations it is obtained a closed system of two ordinary differential equations describing macroscopic cosmological evolution of the isotropic space-flat Universe…

General Relativity and Quantum Cosmology · Physics 2016-08-24 Yurii Ignat'ev

The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…

Astrophysics · Physics 2008-11-26 J. Besprosvany

In our present work, we study the evolution of the universe by assuming an interacting dark energy model, where dark energy interacts with matter. Basing on this model, first we calculated the dark energy density parameter and using this we…

General Relativity and Quantum Cosmology · Physics 2019-12-30 Debasis Sahu , Bibekananda Nayak

Dark energy has a dramatic effect on the dynamics of the universe, causing the recently discovered acceleration of the expansion. The dynamics are also central to the behavior of the growth of large scale structure, offering the possibility…

Astrophysics · Physics 2009-11-07 Eric V. Linder , Adrian Jenkins

Interactions between dark matter and dark energy with a given equation of state are known to modify the cosmic dynamics. On the other hand, the strength of these interactions is subject to strong observational constraints. Here we discuss a…

Astrophysics · Physics 2015-05-13 Winfried Zimdahl

The principles of General Relativity allow for a non-vanishing cosmological constant, which can possibly be interpreted at least partially in terms of quantum-fluctuations of matter fields. Depending on sign and magnitude it can cause…

Astrophysics · Physics 2007-05-23 Domenico Giulini , Norbert Straumann

Physics invites the idea that space contains energy whose gravitational effect approximates that of Einstein's cosmological constant, Lambda; nowadays the concept is termed dark energy or quintessence. Physics also suggests the dark energy…

Astrophysics · Physics 2008-11-26 P. J. E. Peebles , Bharat Ratra

We consider a generic description of interacting dynamical Dark Energy, characterized by an equation of state with a time dependent coefficient $w(t)$, and which may interact with both radiation and matter. Without referring to any…

General Relativity and Quantum Cosmology · Physics 2019-08-20 Marco Bonici , Nicola Maggiore

In this article, we study the effect of the universe accelerating expansion on the structure of the general relativistic thick disks. Hence, by applying a conformal transformation on the metric of a static disk in isotropic coordinates, we…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Senobar Doostali , Alireza Mirzaee , Reza Ramezani Arani , Salman Abarghouei Nejad