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Related papers: Dark Energy From The Gravity Vacuum

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The stress-energy tensor of the quantum vacuum is studied for the particular case of quantum electrodynamics (QED), that is a fictituous universe where only the electromagnetic and the electron-positron fields exist. The integrals involved…

General Relativity and Quantum Cosmology · Physics 2015-05-12 Emilio Santos

The cosmological constant problem is explained by a theory based on the discrete space-time hypothesis. The calculated cosmological constant value is of the order of 10^-52[m]^-2 or equivalent to about 0.7 of the critical mass density. It…

Astrophysics · Physics 2007-05-23 H. M. Mok

We argue that, when coupled to Einstein's theory of gravity, the Yukawa theory may solve the cosmological constant problem in the following sense: The radiative corrections of fermions generate an effective potential for the scalar field,…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Tomislav Prokopec

In this paper we study the cosmological constant emerging from the Wheeler-DeWitt equation as an eigenvalue of the related Sturm-Liouville problem. We employ Gaussian trial functionals and we perform a mode decomposition to extract the…

General Relativity and Quantum Cosmology · Physics 2011-03-22 Remo Garattini , Piero Nicolini

We argue that the cosmological constant problem can be solved in a braneworld model with infinite-volume extra dimensions, avoiding no-go arguments applicable to theories that are four-dimensional in the infrared. Gravity on the brane…

High Energy Physics - Theory · Physics 2009-07-09 Gia Dvali , Gregory Gabadadze , M. Shifman

A probable solution of the cosmological constant problem was recently found. We propose that dark energy of the Universe is vacuum energy. Our Universe during its expansion is spending its vacuum energy for creation of new quantum states,…

General Physics · Physics 2014-01-21 Vladimir Burdyuzha

We have derived the quantum vacuum pressure P_vac as a primary entity, removing a trivial and a gauge terms from the cosmological constant-like part (the zeroth term) of the effective action for a free matter field. The quantum vacuum…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Bogusław Broda , Michał Szanecki

We revisit the theory of background fields constructed on the BRST-algebra of a spinning particle with $\mathcal{N}=4$ worldline supersymmetry, whose spectrum contains the graviton but no other fields. On a generic background, the closure…

High Energy Physics - Theory · Physics 2022-03-14 Daniel Bockisch , Ivo Sachs

We discuss models that can account for today's dark energy. The underlying cosmological constant may be Planck scale but starts as a redundant coupling which can be eliminated by a field redefinition. The observed vacuum energy arises when…

High Energy Physics - Theory · Physics 2008-11-26 Puneet Batra , Kurt Hinterbichler , Lam Hui , Daniel Kabat

In the framework of an effective field theory of general relativity a model of scalar and vector bosons interacting with the metric field is considered. It is shown in the framework of a two-loop order calculation that for the cosmological…

High Energy Physics - Theory · Physics 2019-08-30 J. Gegelia , Ulf-G. Meißner

The common nature of the dark sector - dark energy and dark matter - as shown in [1] follows readily from the consideration of generalized Newtonian potential as a weak-field General Relativity. That generalized potential satisfying the…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 V. G. Gurzadyan , A. Stepanian

The Cosmological Constant Problem is re-examined from an effective field theory perspective. While the connection between gravity and particle physics has not been experimentally probed in the quantum regime, it is severely constrained by…

High Energy Physics - Phenomenology · Physics 2009-10-30 Raman Sundrum

According to recent observations, the Dark Energy would represent 70% of the content of our Universe. The most popular way to account for this Dark Energy make use of the Cosmological Constant introduced by Einstein. However, some…

General Physics · Physics 2018-04-04 Bernard Castaing

The work shows that the associated Einstein like gravity for the Klein-Gordon field shows the spontaneous emergence of the cosmological pressure tensor density (CPTD) that in the classical limit leads to the cosmological constant (CC). Even…

General Physics · Physics 2020-07-07 Piero Chiarelli

In four dimensional gravity theory, the Barbero-Immirzi parameter has a topological origin, and can be identified as the coefficient multiplying the Nieh-Yan topological density in the gravity Lagrangian, as proposed by Date et al.[1].…

General Relativity and Quantum Cosmology · Physics 2013-07-29 Sandipan Sengupta

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…

Astrophysics · Physics 2009-03-12 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

The holographic dark energy model is obtained from a cosmological constant generated by generic quantum gravity effects giving a minimum length. By contrast, the usual bound for the energy density to be limited by the formation of a black…

High Energy Physics - Theory · Physics 2016-05-25 Horatiu Nastase

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

A nonlocal quantum gravity theory is presented which is finite and unitary to all orders of perturbation theory. Vertex form factors in Feynman diagrams involving gravitons suppress graviton and matter vacuum fluctuation loops by…

High Energy Physics - Theory · Physics 2011-08-17 J. W. Moffat

We assume the cosmological dark sector to consist of pressureless matter and holographic dark energy with a cutoff length proportional to the Ricci scale. The requirement of separate energy-momentum conservation of the components is shown…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Sergio del Campo , Júlio. C. Fabris , Ramón Herrera , Winfried Zimdahl
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