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Cosmological constant problem (in its various versions) is arguably the deepest gap in our understanding of theoretical physics, the solution to which may very likely require revisiting the Einstein theory of gravity. In this letter, I…

Astrophysics · Physics 2008-07-18 Niayesh Afshordi

An exact solution of the current-free Einstein-Maxwell equations with the cosmological constant is presented. The solution is of Petrov type D, includes the negative cosmological constant, and could be a ``background addition'' to the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. K. Kowalczynski

We consider extra compact dimensions as the origin of a cosmological universal energy density in the regular dimensions, with only graviton fields propagating in the compact space dimensions. The quantum zero point energy originating from…

General Relativity and Quantum Cosmology · Physics 2015-09-03 Vikram Soni , Naresh Dadhich , Rathin Adhikari

In this essay, we present a new understanding of the cosmological constant problem, built upon the realization that the vacuum energy density can be expressed in terms of a phase space volume. We introduce a UV-IR regularization which…

High Energy Physics - Theory · Physics 2023-03-31 Laurent Freidel , Jerzy Kowalski-Glikman , Robert G. Leigh , Djordje Minic

We outline the evaluation of the cosmological constant in the framework of the standard field-theoretical treatment of vacuum energy and discuss the relation between the vacuum energy problem and the gauge-group spontaneous symmetry…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. A. Andrianov , F. Cannata , P. Giacconi , A. Yu. Kamenshchik , R. Soldati

A general formula for the metric as an explicit function of the generic energy-momentum tensor is given which satisfies static plane symmetric Einstein's equations with cosmological constant.In order to illustrate it, the solutions for the…

General Relativity and Quantum Cosmology · Physics 2013-08-26 Leandro G. Gomes

The problem of cosmological constant and vacuum energy is usually thought of as the subject of general relativity. However, the vacuum energy is important for the Universe even in the absence of gravity, i.e. in the case when the Newton…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. E. Volovik

We trace the origin of the cosmological constant problem to the assumption that Newton's constant $G$ sets the scale for cosmology. And then we show that once this assumption is relaxed, the very same cosmic acceleration which has served to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Philip D. Mannheim

The hypothesis is proposed that under the approximation that the quantum equations of motion reduce to the classical ones, the quantum vacuum also reduces to the classical vacuum--the empty space. The vacuum energy of QED is studied under…

High Energy Physics - Theory · Physics 2007-05-23 Shi Qi

The theoretical vacuum energy density estimated on the basis of the Standard Model of particle physics and very general quantum assumptions is 59 to 123 orders of magnitude larger than the measured vacuum energy density for the observable…

General Physics · Physics 2016-07-04 R. L. Oldershaw

We are at a specific period of modern cosmology, during which the large increase of the amount of data leads to the idea that the determination of cosmological parameters has been achieved with a rather good precision. There is a large…

Astrophysics · Physics 2017-08-23 A. Blanchard

The value of the cosmological constant arising from a crystalline model for vacuum cosmic space with lattice parameter of the order of the neutron radius [1] has been calculated. The model allows to solve, in an easy way, the problem of the…

We show that the presence of a temporal electromagnetic field on cosmological scales generates an effective cosmological constant which can account for the accelerated expansion of the universe. Primordial electromagnetic quantum…

Astrophysics · Physics 2011-07-13 Jose Beltran Jimenez , Antonio L. Maroto

The cosmological constant problem arises because the magnitude of vacuum energy density predicted by quantum mechanics is about 120 orders of magnitude larger than the value implied by cosmological observations of accelerating cosmic…

General Relativity and Quantum Cosmology · Physics 2018-09-19 Samuel S. Cree , Tamara M. Davis , Timothy C. Ralph , Qingdi Wang , Zhen Zhu , William G. Unruh

The typical scalar field theory has a cosmological constant problem. We propose a generic mechanism by which this problem is avoided at tree level by embedding the theory into a larger theory. The metric and the scalar field coupling…

High Energy Physics - Phenomenology · Physics 2012-07-11 Roman V. Buniy , Thomas W. Kephart

The cosmological constant is not an absolute constant. The gravitating part of the vacuum energy is adjusted to the energy density of matter and to other types of the perturbations of the vacuum. We discuss how the vacuum energy responds…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. E. Volovik

We explore possible cosmological consequences of a running Newton's constant $ G ( \Box ) $, as suggested by the non-trivial ultraviolet fixed point scenario in the quantum field-theoretic treatment of Einstein gravity with a cosmological…

General Relativity and Quantum Cosmology · Physics 2011-09-08 Herbert W. Hamber , Reiko Toriumi

It is shown to all orders of perturbation theory that in the effective field theory of general relativity the condition of vanishing of the vacuum energy leads to the same value of the cosmological constant, viewed as a parameter of the…

High Energy Physics - Theory · Physics 2026-01-19 E. Epelbaum , J. Gegelia , Ulf-G. Meißner

In this colloquium-level account, I describe the cosmological constant problem: why is the energy of empty space at least 60 orders of magnitude smaller than several known contributions to it from the Standard Model of particle physics? I…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-06 Raphael Bousso

A short review about vacuum energy and the cosmological constant is presented. The observed acceleration of the universe introduces a new meV energy scale. The problem is that, theoretically, the predicted vacuum energy is many orders of…

High Energy Physics - Theory · Physics 2009-09-01 Eduard Masso
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