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Related papers: Observed Smooth Energy Fitted by Parametrized Quin…

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Multifield models with a curved field space have already been shown to be able to provide viable quintessence models for steep potentials that satisfy swampland bounds. The simplest dynamical systems of this type are obtained by coupling…

High Energy Physics - Theory · Physics 2020-10-28 Michele Cicoli , Giuseppe Dibitetto , Francisco G. Pedro

We discuss an alternative approach to quintessence modifying the usual equation of state of the cosmological fluid in order to see if going further than the approximation of perfect fluid allows to better reproduce the available data. We…

Astrophysics · Physics 2008-11-26 S. Capozziello , V. F. Cardone , S. Carloni , S. De Martino , M. Falanga , A. Troisi , M. Bruni

For a flat universe presently dominated by static or dynamic vacuum energy, cosmological constant (LCDM) or quintessence (QCDM), we calculate the asymptotic collapsed mass fraction as function of the present ratio of smooth energy to matter…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sidney A. Bludman

The equation of state characterizing the dark energy component is constrained by combining Chandra observations of the X-ray luminosity of galaxy clusters with independent measurements of the baryonic matter density and the latest…

Astrophysics · Physics 2008-11-26 J. A. S. Lima , J. V. Cunha , J. S. Alcaniz

The issues of quintessence and cosmic acceleration can be discussed in the framework of theories which do not include necessarily scalar fields. It is possible to define pressure and energy density for new components considering effective…

Astrophysics · Physics 2008-11-26 S. Capozziello , S. Carloni , A. Troisi

We derive the slow-roll conditions for a non-minimally coupled scalar field (extended quintessence) during the radiation/matter dominated era extending our previous results for thawing quintessence. We find that the ratio…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Takeshi Chiba , Masaru Siino , Masahide Yamaguchi

A fictitious discussion is taken as a point of origin to present novel physical insight into the nature of gauge theory and the potential energy of QCD and QED at short distance. Emphasized is the considerable freedom in the cut-off…

High Energy Physics - Phenomenology · Physics 2016-09-06 Hans-Christian Pauli

Today it still remains a challenge whether quantum mechanics has an underlying statistical explanation or not. While there are and were a lot of models trying to explain quantum phenomena with statistical methods these all failed on certain…

Quantum Physics · Physics 2016-12-05 Gabor Helesfai

The symmetry energy of nuclear matter is a fundamental ingredient in the investigation of exotic nuclei, heavy-ion collisions and astrophysical phenomena. A recently developed quantum statistical (QS) approach that takes the formation of…

Nuclear Experiment · Physics 2015-06-18 K. Hagel , J. B. Natowitz , G. Röpke

We analyse the constraints that can be placed on a cosmological constant or quintessence-like component by combining observations of Type Ia supernovae with measurements of anisotropies in the cosmic microwave background. We use the recent…

Astrophysics · Physics 2009-10-31 G. Efstathiou

Many ambitious experiments have been proposed to constrain dark energy and detect its evolution. At present, observational constraints are consistent with a cosmological constant and there is no firm evidence for any evolution in the dark…

Astrophysics · Physics 2009-02-26 Sirichai Chongchitnan , George Efstathiou

The classical square well potential is smoothed with a finite range smoothing function in order to get a new simple strictly finite range form for the phenomenological nuclear potential. The smoothed square well form becomes exactly zero…

Nuclear Theory · Physics 2017-08-02 Péter Salamon , Tamás Vertse

Smoothing is an estimation technique that takes into account both past and future observations, and can be more accurate than filtering alone. In this Letter, a quantum theory of smoothing is constructed using a time-symmetric formalism,…

Quantum Physics · Physics 2009-07-14 Mankei Tsang

In this comment, we show explicitly that the phenomenological model in which the quintessence field depends linearly on the energy density of the spatial curvature can provide acceleration for the universe, contrary to recent claims it…

Astrophysics · Physics 2007-05-23 Urbano Franca

We study flat Friedmann-Robertson-Walker (FRW) models with a perfect fluid matter source and a scalar field non minimally coupled to matter having a double exponential potential. It is shown that the scalar field almost always diverges to…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Koralia Tzanni , John Miritzis

In this paper we investigate the quintessence model with a minimally coupled scalar field in the context of recent supernovae observations. By choosing a particular form of the deceleration parameter q, which gives an early deceleration and…

Astrophysics · Physics 2009-11-11 Narayan Banerjee , Sudipta Das

Assuming a flat Friedmann-Robertson-Walker cosmology with a single perfect fluid, we propose a pressure-density ratio that evolves as a specific universal function of the scale parameter. We show that such a ratio can indeed be consistent…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Golam Mortuza Hossain , Parthasarathi Majumdar

Quantifying coherence is an essential endeavour for both quantum foundations and quantum technologies. Here the robustness of coherence is defined and proven a full monotone in the context of the recently introduced resource theories of…

We present updated constraints on an interacting dark energy - dark matter model with pure momentum transfer, where dark energy is in the form of a quintessence scalar field with an exponential potential. We run a suite of MCMC analyses…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-09 Alkistis Pourtsidou

Quintessence with a potential motivated by supergravity (SUGRA) exhibits several intriguing features. Depending on its initial conditions, it can behave either as dynamical dark energy or effectively as a cosmological constant. Moreover,…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Jincheng Wang , Hongwei Yu , Puxun Wu
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