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Related papers: Vacuum Structure and Dark Energy

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The acceleration of the cosmic expansion is a fundamental challenge to standard models of particle physics and cosmology. The new physics of dark energy may lie in the nature of gravity, the quantum vacuum, or extra dimensions. I give a…

Astrophysics · Physics 2010-02-17 Eric V. Linder

The presence of dark energy in the Universe is inferred directly and indirectly from a large body of observational evidence. The simplest and most theoretically appealing possibility is the vacuum energy density (cosmological constant).…

Astrophysics · Physics 2008-11-26 J. S. Alcaniz

On the basis of our quantum cosmological approach we show that there can be two previously unknown types of collective states in the universe. One of them relates to a gravitational field, another is connected with a matter (scalar) field…

Astrophysics · Physics 2007-05-23 V. E. Kuzmichev , V. V. Kuzmichev

It is commonly agreed that the electromagnetic vacuum is not empty but filled with virtual photons. This leads to effects like Lamb shift and spontaneous emission. Here we argue that if the vacuum has virtual photons it might mean that it…

Quantum Physics · Physics 2023-03-22 Karol Gietka

We carried out a study of the properties of the $\lambda \phi^4$ field solutions. By constructing Gaussian wave packets to calculate the $S$ matrix, we show that the probability of the vacuum unbroken state transfers to the broken state is…

High Energy Physics - Theory · Physics 2011-06-16 B. Pan

To explain the acceleration of the cosmological expansion researchers have considered an unusual form of mass-energy generically called dark energy. Dark energy has a ratio of pressure over mass density which obeys $w=p/\rho <-1/3$. This…

High Energy Physics - Theory · Physics 2008-12-19 Max Chaves , Douglas Singleton

It is suggested that the vacuum expectation of the quantum vacuum energy-momentum is zero, but quantum fluctuations give rise to a space-time curvature equivalent to that of a cosmological constant or dark energy. Calculations within…

General Relativity and Quantum Cosmology · Physics 2009-02-26 Emilio Santos

The quantum model of the homogeneous, isotropic, and spatially closed universe predicts an existence of two types of collective quantum states in the universe. The states of one type characterize a gravitational field, the others describe a…

Astrophysics · Physics 2007-05-23 V. E. Kuzmichev , V. V. Kuzmichev

We study physics concerning the cosmological constant problem in the framework of effective field theory and suggest that a dominant part of dark energy can originate from gravitational corrections of vacuum energy, under the assumption…

High Energy Physics - Theory · Physics 2017-02-24 Yugo Abe , Masaatsu Horikoshi , Yoshiharu Kawamura

In this dissertation, the nature of Dark Energy (DE) is examined from both theoretical and phenomenological perspectives. The possibility of DE being a dynamic quantity in quantum field theory (QFT) in curved spacetime is studied. The…

General Relativity and Quantum Cosmology · Physics 2023-11-14 Cristian Moreno-Pulido

Observations suggest that nearly seventy per cent of the energy density in the universe is unclustered and exerts negative pressure. Theoretical understanding of this component (`dark energy'), which is driving an accelerated expansion of…

Astrophysics · Physics 2007-05-23 T. Padmanabhan

We analyse three cosmological scenarios with interaction in the dark sector, which are particular cases of a general expression for the energy flux from vacuum to matter. In the first case the interaction leads to a transition from an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-31 L. P. Chimento , S. Carneiro

The vacuum is filled with complex scalar fields, such as the Higgs field. These fields serve as order parameters for superfluidity (quantum phase coherence over macroscopic distances), making the entire universe a superfluid. We review a…

General Relativity and Quantum Cosmology · Physics 2013-11-18 Kerson Huang

The metastable dark energy scenario is revisited by assuming that the current false vacuum energy density is the remnant from a primeval inflationary stage. The zero temperature scalar field potential is here described by an even power…

General Relativity and Quantum Cosmology · Physics 2020-09-01 J. A. S. Lima , G. J. M. Zilioti , L. C. T. Brito

Recent cosmological and astrophysical observations point out that the Universe is in accelerating expansion and filled up with non-luminous matter. In order to explain the observed large scale structures and this accelerating behavior one…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-23 S. Capozziello , G. Lambiase

We uncover the general mechanism producing the dark energy(DE). This is only based on well known quantum physics and cosmology. We show that the observed DE originates from the cosmological quantum vacuum of light particles which provides a…

Astrophysics · Physics 2023-04-05 Hector J. de Vega , Norma G. Sanchez

We analyze the oscillations of Rydberg atoms in the framework of quantum field theory and we reveal non-trivial vacuum energy which has the equation of state of the dark matter. This energy is similar to that expected for mixed neutrinos…

High Energy Physics - Phenomenology · Physics 2021-01-19 A. Capolupo , S. M. Giampaolo , G. Lambiase , A. Quaranta

Dark energy is one of the mysteries of modern science. It is unlike any known form of matter or energy and has been detected so far only by its gravitational effect of repulsion. Owing to its effects being discernible only at very very…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-25 Aruna Kesavan

The universe should be dark at energies exceeding $\sim 5\times 10^{19}$ eV. This simple but solid prediction of our best known particle physics is not confirmed by observations, that seem to suggest a quite different picture. Numerous…

Astrophysics · Physics 2007-05-23 Pasquale Blasi

Dark energy appears to be the dominant component of the physical Universe, yet there is no persuasive theoretical explanation for its existence or magnitude. The acceleration of the Universe is, along with dark matter, the observed…

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