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Related papers: Quantum Kinetic Equations and Cosmology

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In this paper, our focus is on investigating the impact of cosmological constant on relativistic quantum systems comprising spin-0 scalar particles. Our analysis centers around the Klein-Gordon equation, and we obtain both approximate and…

General Relativity and Quantum Cosmology · Physics 2024-04-02 Faizuddin Ahmed , Abdelmalek Bouzenada

We explore two hypotheses. First, the possibility that the quantum vacuum energy density of the Casimir effect contributes to a (local) gravitational vacuum energy density. Second, the possibility that a change in the gravitational coupling…

High Energy Physics - Theory · Physics 2023-11-14 Benjamin Koch , Christian Käding , Mario Pitschmann , René Sedmik

The cosmological constant combined with Planck's constant and the speed of light implies a quantum of mass of approximately 2 x 10^{-65}g. This follows either from a generic dimensional analysis, or from a specific analysis where the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Paul S. Wesson

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

Recently, a lot of attention has been paid to the modifications of the power spectrum of primordial fluctuations caused by quantum cosmology effects. The origin of these modifications are corrections to the Mukhanov-Sasaki equations that…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Laura Castelló Gomar , Mercedes Martín-Benito , Guillermo A. Mena Marugán

In this paper we discuss a possible cosmological time evolution of fundamental constants from the theoretical and experimental point of views. On the theoretical side, we explain that such a cosmological time evolution is actually something…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Xavier Calmet , Matthias Keller

The Standard Model of particle physics and the theory of General Relativity (GR) currently provide a good description of almost all phenomena of particle physics and gravitation that have received controlled experimental tests. However, the…

Atomic Physics · Physics 2009-01-23 Thomas Dent

Small effects of quantum gravity on the scale $\sim 10^{-3} eV$ and their cosmological consequences are discussed and compared with observations of supernovae 1a, gamma-ray bursts and galaxies.

High Energy Physics - Theory · Physics 2011-11-10 Michael A. Ivanov

The cosmological constant problem is examined under the assumption that the extrinsic curvature of the space-time contributes to the vacuum. A compensation mechanism based on a variable cosmological term is proposed. Under a suitable…

General Relativity and Quantum Cosmology · Physics 2009-09-25 M. D. Maia , G. S. Silva

Inspired by Einstein's Strong Principle of Equivalence we consider the effects of quantum mechanics to the gravity-like phenomena experienced by an observer in a uniformly accelerating motion in flat spacetime. Among other things, our model…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Jarmo Mäkelä

Whereas the total energy in zero-point fluctuations of the particle physics vacuum gives rise to the cosmological constant problem, differences in the vacuum give rise to real physical phenomena, such as the Casimir effect. Hence we…

Astrophysics · Physics 2007-05-23 R. R. Caldwell

A classical dynamical system in a four-dimensional Euclidean space with universal time is considered. The space is hypothesized to be originally occupied by a uniform substance, pictured as a liquid, which at some time became supercooled.…

High Energy Physics - Theory · Physics 2013-06-19 Michael Grady

We present an extension of general relativity in which the cosmological constant becomes dynamical and turns out to be conjugate to the Chern-Simons invariant of the Ashtekar connection on a spatial slicing. The latter has been proposed in…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Stephon Alexander , Joao Magueijo , Lee Smolin

Taking a hint from Dirac's large number hypothesis, we note the existence of cosmic combined conservation laws that work to cosmologically long time. We thus modify or generalize Einstein's theory of general relativity with fixed…

General Relativity and Quantum Cosmology · Physics 2014-11-17 H. W. Peng

We show that the fluctuations of quantum fields as seen by late comoving observers are significantly influenced by the history of the early Universe, and therefore they transmit information about the nature of spacetime in timescales when…

General Relativity and Quantum Cosmology · Physics 2015-10-13 Ana Blasco , Luis J. Garay , Mercedes Martin-Benito , Eduardo Martin-Martinez

We have critically compared different approaches to the cosmological constant problem, which is at the edge of elementary particle physics and cosmology. This problem is deeply connected with the difficulties formulating a theory of quantum…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stefan Nobbenhuis

A homogeneous and isotropic cosmological model with a positive cosmological constant is considered. The matter sector is given by a massless scalar field, which can be used as an internal time to deparametrize the theory. The idea is to…

General Relativity and Quantum Cosmology · Physics 2015-04-28 David Brizuela

The unification of gravity to the other forces has been a major problem for most of the last century. I use a modification to Newtonian gravitation to extract the strong and weak nuclear coupling constants. Some of the possible implications…

General Physics · Physics 2007-05-23 Shantilal G. Goradia

The Newtonian gravitational constant has still 150 parts per million of uncertainty. This paper examines the linear and nonlinear equations governing the rotational dynamics of the torsion gravitational balance. A nonlinear effect modifying…

Classical Physics · Physics 2008-01-07 Michele Rossi , Lorenzo Zaninetti

An attractive and simple hypothesis for the formation of large-scale structure is that it developed by gravitational instability from primordial fluctuations with an initially Gaussian probability distribution. Non-linear gravitational…

Astrophysics · Physics 2015-06-24 Ewa Luiza Lokas , Roman Juszkiewicz , David Weinberg , Francois Bouchet
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