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Related papers: The Averaging Problem in Cosmology and Macroscopic…

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In the present article, which is the first part of a work in three parts, we build an equation of quantum gravity. This equation is tensorial, is equivalent to general relativity in vacuum, but differs completely from general relativity…

General Physics · Physics 2007-11-25 Christophe Real

In a geometric unified theory there is an energy momentum equation, apart from the field equations and equations of motion. The general relativity Einstein equation with cosmological constant follows from this energy momentum equation for…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Gustavo R. Gonzalez-Martin

The cosmology of general fourth order corrections to Einstein gravity is considered, both for a homogeneous and isotropic background and for general tensor perturbations. It is explicitly shown how the standard cosmological history can be…

General Relativity and Quantum Cosmology · Physics 2011-03-07 William Nelson

The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Albert V. Minkevich

One of the outstanding problems in general relativistic cosmology is that of the averaging. That is, how the lumpy universe that we observe at small scales averages out to a smooth Friedmann-Lemaitre-Robertson-Walker (FLRW) model. The root…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-21 Tharake Wijenayake , Weikang Lin , Mustapha Ishak

I argue that a solution to the cosmological constant problem is to assume that the expectation value of the quantum vacuum stress-energy tensor is proportional to the metric tensor with a negative energy density and positive pressure. This…

General Physics · Physics 2018-05-09 Emilio Santos

Motivated by conventional gauge theories, we consider a theory of gravity in which the Einstein-Hilbert action is replaced by a term that is quadratic in the Riemann tensor. We focus on cosmological solutions to the field equations in flat,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. N. Lasenby , C. J. L. Doran , R. Heineke

One of the possible applications of macroscopic Einstein equations has been considered. So, the nonsingular isotropic and uniform cosmological model is built. The cosmological consequences of this model are agree with conclusions of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Zakharov

The standard model of cosmology assumes that the Universe can be described to hover around a homogeneous-isotropic solution of Einstein's general theory of relativity. This description needs (sometimes hidden) hypotheses that restrict the…

General Relativity and Quantum Cosmology · Physics 2018-12-21 Thomas Buchert

Cosmology is built on a relativistic understanding of gravity, where the geometry of the Universe is dynamically determined by matter and energy. In the cosmological concordance model, gravity is described by General Relativity, and it is…

General Relativity and Quantum Cosmology · Physics 2024-07-26 Theodore Anton

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

The construction of an averaged theory of gravity based on Einstein's General Relativity is very difficult due to the non-linear nature of the gravitational field equations. This problem is further exacerbated by the difficulty in defining…

General Relativity and Quantum Cosmology · Physics 2010-04-16 R. J. van den Hoogen

It seems likely that the generalized Einstein equations are not complete and only partly account for the effect on the Universe dynamics of that part of the energy of the space environment the change of which is purely geometric. There are…

General Physics · Physics 2012-06-04 A. V. Klimenko , V. A. Klimenko

We discuss how the modifications of the standard Einstein's equations needed to support the cosmological bounce can at the same time lead to vanishing of the well known cosmological constant problem, while also studying the effects of…

General Relativity and Quantum Cosmology · Physics 2025-01-24 Petar Pavlović , Marko Sossich

If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a `dark energy'. However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on…

Astrophysics · Physics 2008-11-26 Aseem Paranjape , T. P. Singh

There is a set of first-order differential equations for the curvature tensor in general relativity (the curvature equations or CEs for short) that are strikingly similar to the Maxwell equations of electrodynamics. This paper considers…

General Relativity and Quantum Cosmology · Physics 2009-01-29 Richard J. Cook

We consider the problem of building inhomogeneous cosmological models in scalar-tensor theories of gravity. This starts by splitting the field equations of these theories into constraint and evolution equations, and then proceeds by…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Jessie Durk , Timothy Clifton

We present a new approach for averaging in general relativity and cosmology. After a short review of the theory originally taken from the equivalence problem, we consider two ways how to deal with averaging based on Cartan scalars. We apply…

General Relativity and Quantum Cosmology · Physics 2014-05-23 Petr Kaspar , Otakar Svitek

The universal character of the gravitational interaction provided by the equivalence principle motivates a geometrical description of gravity. The standard formulation of General Relativity \`a la Einstein attributes gravity to the…

General Relativity and Quantum Cosmology · Physics 2021-04-13 Jose Beltrán Jiménez , Lavinia Heisenberg , Tomi Sebastian Koivisto , Simon Pekar

We consider static cosmological solutions along with their stability properties in the framework of a recently proposed theory of massive gravity. We show that the modifcation introduced in the cosmological equations leads to several new…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Luca Parisi , Ninfa Radicella , Gaetano Vilasi