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Related papers: Cosmology of {\Lambda}-term (vacuum component)

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An accelerated universe should naturally have a vacuum energy density determined by its dynamical curvature. The cosmological constant is most likely a temporary description of a dynamical variable that has been drastically evolving from…

General Relativity and Quantum Cosmology · Physics 2015-10-28 Joan Sola

We develop a cosmological theory in which the evolution of the universe is controlled by the cosmological constant and dominated by the associated vacuum energy. The universe starts as a classical de Sitter space with an infinite effective…

General Physics · Physics 2023-03-21 J. M. Greben

In this year, in which we celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, we are still facing the crucial question whether $\Lambda$ is truly a fundamental constant or a mildly evolving…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-27 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

A generalized quintessence model is presented which corresponds to a richer vacuum structure that, besides a time-dependent, slowly varying scalar field, contains a varying cosmological term. From first principles we determine a number of…

Astrophysics · Physics 2009-10-31 Pedro F. Gonzalez-Diaz

We propose a new approach for multiverse analysis based on computational complexity, which leads to a new family of "computational" measure factors. By defining a cosmology as a space-time containing a vacuum with specified properties (for…

High Energy Physics - Theory · Physics 2018-04-18 Frederik Denef , Michael R. Douglas , Brian Greene , Claire Zukowski

In Loop Quantum Gravity mathematically rigorous models of full quantum gravity were proposed. In this paper we study a cosmological sector of one of the models describing quantum gravity with positive cosmological constant coupled to…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Marcin Kisielowski

The traditional "explanation" for the observed acceleration of the universe is the existence of a positive cosmological constant. However, this can hardly be a truly convincing explanation, as an expanding universe is not expected to have a…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Joan Sola

We consider general relativity with a cosmological constant as a perturbative expansion around a completely solvable diffeomorphism invariant field theory. This theory is the $\Lambda\to\infty$ limit of general relativity. This allows an…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rodolfo Gambini , Jorge Pullin

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 use the quantum unimodular theory of gravity to relate the value of the cosmological constant, $\Lambda$, and the energy scale for the emergence of cosmological classicality. The fact that $\Lambda$ and unimodular time are complementary…

High Energy Physics - Theory · Physics 2023-01-04 Niayesh Afshordi , João Magueijo

We investigate the gravitational property of the quantum vacuum by treating its large energy density predicted by quantum field theory seriously and assuming that it does gravitate to obey the equivalence principle of general relativity. We…

General Relativity and Quantum Cosmology · Physics 2019-04-22 Qingdi Wang , Zhen Zhu , William G. Unruh

We have found that the hierarchial problems appearing in cosmology is a manifestation of the quantum nature of the universe. The universe is still described by the same formulae that once hold at Planck's time. The universe is found to be…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Arbab I. Arbab

In this paper we study the description of the Universe based on the low energy superstring theory modified by the Loop Quantum Gravity effects.This approach was proposed by De Risi et al. in the Phys. Rev. D {\bf 76} (2007) 103531. We show…

High Energy Physics - Theory · Physics 2008-11-26 Jakub Mielczarek , Marek Szydlowski

We investigate the dynamics of the FLRW flat cosmological models in which the vacuum energy varies with redshift. A particularly well motivated model of this type is the so-called quantum field vacuum, in which both kind of terms $H^{2}$…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Spyros Basilakos

Physics invites the idea that space contains energy whose gravitational effect approximates that of Einstein's cosmological constant, Lambda; nowadays the concept is termed dark energy or quintessence. Physics also suggests the dark energy…

Astrophysics · Physics 2008-11-26 P. J. E. Peebles , Bharat Ratra

Universe structure emerges in the unreduced, complex-dynamic interaction process with the simplest initial configuration (two attracting homogeneous fields, quant-ph/9902015). The unreduced interaction analysis gives intrinsically creative…

General Physics · Physics 2007-05-23 Andrei P. Kirilyuk

The standard model of the universe is further completed back in time before inflation in agreement with observations, classical-quantum gravity duality and quantum space-time. Quantum vacuum energy bends the space-time and produces a…

General Physics · Physics 2022-04-25 Norma G. Sanchez

Based on a more careful canonical analysis, we motivate a reduced quantization - in the sense of superspace quantization - of slightly inhomogeneous cosmology in place of the Dirac quantization in the existing literature, and provide it in…

General Relativity and Quantum Cosmology · Physics 2016-04-05 Edward Anderson

For more seventy years physicists have appreciated that Nature's vacuum is far from empty. The discovery of the Lamb shift in Hydrogen provided dramatic verification of the reality of the quantum vacuum. The advent of gauge theories has led…

Astrophysics · Physics 2007-05-23 Michael S. Turner

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
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