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Related papers: On Topological Defects and Cosmological Constant

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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

The paper deals with the scale discrepancy between the observed vacuum energy in cosmology and the theoretical quantum vacuum energy (cosmological constant problem). Here, we demonstrate that Einstein's equation and an analogy to particle…

General Physics · Physics 2019-02-08 Christian Henke

Many particle physics models of matter admit solutions corresponding to stable or long-lived topological defects. In the context of standard cosmology it is then unavoidable that such defects will form during phase transitions in the very…

High Energy Physics - Phenomenology · Physics 2009-10-31 Robert H. Brandenberger

Possible analogies between vacuum state and quantum fluid provide a model to study vacuum energy density induced by thermal corrections, space-time curvature, boundary conditions and quantum back-reaction. We find that vacuum energy density…

High Energy Physics - Theory · Physics 2012-06-19 J. A. Sanchez-Monroy , C. J. Quimbay

An artificial scale of observable cosmological constant is dynamically related to its natural bare value due to an installation of relevant coherent state for the inflationary field in a finite volume of early Universe, because of…

General Relativity and Quantum Cosmology · Physics 2014-01-15 V. V. Kiselev

If Mach's Principle explains the Newtonian inertial reaction to acceleration then the role of the 'fixed stars' should also be manifest through Hamilton's formulation of mechanics. This consistency may be achieved if the expression for…

Astrophysics · Physics 2007-05-23 Scott Funkhouser

The standard formulation of the cosmological constant problem is based on one critical assumption---the spacetime is homogeneous and isotropic, which is true only on cosmological scales. However, this problem is caused by extremely small…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Qingdi Wang

The origins of the cosmological constant are discussed from the perspective of the imaginary-time field theory. The concept of the thermal time, which is related to the Tolman-Ehrehfest relation, and the conformal invariance of the actions…

General Relativity and Quantum Cosmology · Physics 2013-11-28 Yi-Cheng Huang

The quantum gravitational contribution to the renormalization group behavior of the electric charge in Einstein-Maxwell theory with a cosmological constant is considered. Quantum gravity is shown to lead to a contribution to the running…

High Energy Physics - Theory · Physics 2008-11-26 David J. Toms

The cosmological constant problem is the principal obstacle in the attempt to interpret dark energy as the quantum vacuum energy. We suggest that the obstacle can be removed, i.e. that the cosmological constant problem can be resolved by…

General Physics · Physics 2012-01-24 Dragan Slavkov Hajdukovic

Lord Kelvin believed that the electromagnetic aether must also generate gravity. Presently, we have no methods to determine the density of the electromagnetic aether, or we say the $\Omega(1)$ substratum. Thus, we also suppose that vacuum…

General Physics · Physics 2022-09-22 Xiao-Song Wang

Giving up Einstein's assumption, implicit in his 1916 field equations, that inertial mass, even in its appearance as energy, is equivalent to active gravitational mass and therefore is a source of gravity allows revising the field equations…

General Relativity and Quantum Cosmology · Physics 2016-03-18 Homer G. Ellis

Standard cosmology has long been plagued by a number of persistent problems. The origin of the apparent acceleration of the cosmic expansion remains enigmatic. The cosmological constant has been reintroduced as a free parameter with a value…

General Physics · Physics 2023-02-28 Jan O. Stenflo

The paper aims to provide an explanation for the tiny value of the cosmological constant and the low vacuum energy density to represent the dark energy. To accomplish this, we will search for a fundamental principle of symmetry in…

General Relativity and Quantum Cosmology · Physics 2016-11-14 Cláudio Nassif

In this work we review briefly the origin and history of the cosmological constant and its recent reincarnation in the form of the dark energy component of the universe. We also comment on the fundamental problems associated to its…

Astrophysics · Physics 2009-06-23 Antonio Dobado , Antonio L. Maroto

There is some evidence that the Universe is presently undergoing accelerating expansion. This has restored some credit to the scenarios with a non-vanishing cosmological constant. From the point of view of a theory of fundamental…

High Energy Physics - Phenomenology · Physics 2014-11-17 Pierre Binetruy

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

We point out that, due to the nonlinearity of the Einstein equations, a homogeneous approximation in cosmology leads to the appearance of an additional term in the Friedmann equation. This new term is associated with the spatial…

Astrophysics · Physics 2015-06-24 Gyula Bene , Viktor Czinner , Matyas Vasuth

Bouncing models have been proposed by many authors as a completion, or even as an alternative to inflation for the description of the very early and dense Universe. However, most bouncing models contain a contracting phase from a very large…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-31 Rodrigo Maier , Stella Pereira , Nelson Pinto-Neto , Beatriz B. Siffert

The idea that the cosmological term, Lambda, should be a time dependent quantity in cosmology is a most natural one. It is difficult to conceive an expanding universe with a strictly constant vacuum energy density, namely one that has…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Joan Sola
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