English
Related papers

Related papers: Constraining bouncing cosmology caused by Casimir …

200 papers

We discuss certain issues related to the limitations of density parameters for a ``radiation''-like contribution to the Friedmann equation using kinematical or geometrical measurements. We analyse the observational constraint of a negative…

Astrophysics · Physics 2008-11-26 Wlodzimierz Godlowski , Marek Szydlowski

We investigate an evolutional scenario of the FRW universe with the Casimir energy scaling like $(-)(1+z)^4$. The Casimir effect is used to explain the vacuum energy differences (its value measured from astrophysics is so small compared to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Marek Szydlowski , Wlodzimierz Godlowski

We develop here a mechanism that, without making use of a cosmological constant, reproduces an accelerating universe. This is done by taking into account Casimir vacuum energy density, assuming that the underlying theory allows a maximum…

General Relativity and Quantum Cosmology · Physics 2007-05-23 F. Briscese , A. Marciano

A simple model is introduced in which the cosmological constant is interpreted as a true Casimir effect on a scalar field filling the universe (e.g. $\mathbf{R} \times \mathbf{T}^p\times \mathbf{T}^q$, $\mathbf{R} \times \mathbf{T}^p\times…

High Energy Physics - Theory · Physics 2009-10-31 E. Elizalde

A spatially flat Friedmann-Robertson-Walker background with a general scale factor is considered. In this space-time, the energy-momentum tensor of the scalar field with a general curvature coupling parameter is obtained. Using the Thermo…

High Energy Physics - Theory · Physics 2020-07-15 A. F. Santos , S. C. Ulhoa , Faqir C. Khanna

We apply the background field method and the effective action formalism to describe the four-dimensional dynamical Casimir effect. Our picture corresponds to the consideration of quantum cosmology for an expanding FRW universe (the boundary…

High Energy Physics - Theory · Physics 2009-01-14 I. Brevik , K. A. Milton , S. D. Odintsov , K. E. Osetrin

For a Friedman-Robertson-Walker space-time in which the only contribution to the stress-energy tensor comes from the renormalised zero-point energy (i.e. the Casimir energy) of the fundamental fields the evolution of the universe (the scale…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Frank Antonsen , Karsten Bormann

We derive several, detailed relationships in terms of the Friedmann, Robertson, Walker (FRW) generalization which describe the Universe during both the radiation and matter dominated epochs. We explicitly provide for the influence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Ahmet M. Öztaş , Michael L. Smith

Both Stefan-Boltzmann law and the Casimir effect, in a universe described by the FRW metric with zero curvature, are calculated. These effects are described by Thermo Field Dynamics (TFD). The gravitational energy-momentum tensor is defined…

General Relativity and Quantum Cosmology · Physics 2022-04-20 A. F. Santos , S. C. Ulhoa , E. P. Spaniol , Faqir C. Khanna

A scalar self-interacting theory non-linearly coupled with some power of the curvature have a possibility to explain the current smallness of the cosmological constant. Here one concentrate on a massless scalar field in the four-dimensional…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Tomohiro Inagaki

We discuss Casimir effect of a massless, minimally coupled scalar field in a 6D warped flux compactification model and its implications for the hierarchy and cosmological constant problems, which are longstanding puzzles in phenomenology…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Masato Minamitsuji

Most cosmological models studied today are based on the assumption of homogeneity and isotropy. Observationally one can find evidence that supports these assumptions on very large scales, the strongest being the almost isotropy of the…

Astrophysics · Physics 2007-05-23 Christian Sicka , Thomas Buchert , Martin Kerscher

Recent supernovae of type Ia measurements and other astronomical observations suggest that our universe is in accelerating phase of evolution at the present epoch. While a dark energy of unknown form is usually proposed as the most feasible…

Astrophysics · Physics 2008-11-26 Andrzej Borowiec , Wlodzimierz Godlowski , Marek Szydlowski

We construct high-precision models of the Universe that contain radiation, a cosmological constant, and periodically distributed inhomogeneous matter. The density contrasts in these models are allowed to be highly non-linear, and the…

General Relativity and Quantum Cosmology · Physics 2017-02-24 Viraj A. A. Sanghai , Timothy Clifton

This paper discusses the problem of inflation in the context of Friedmann-Robertson-Walker Cosmology. We show how, after a simple change of variables, one can quantize the problem in a way which parallels the classical discussion. The…

High Energy Physics - Theory · Physics 2007-05-23 Marvin Weinstein , Ratin Akhoury

We suggest a new perspective on the Cosmological Constant Problem by scrutinizing its standard formulation. In classical and quantum mechanics without gravity, there is no definition of the zero point of energy. Furthermore, the Casimir…

High Energy Physics - Theory · Physics 2014-09-25 Denis Bernard , André LeClair

In the final few years of his life, Julian Schwinger proposed that the ``dynamical Casimir effect'' might provide the driving force behind the puzzling phenomenon of sonoluminescence. Motivated by that exciting suggestion, we have computed…

High Energy Physics - Theory · Physics 2008-11-26 Kimball A. Milton , Y. Jack Ng

In the standard FRW formalism, the scale factor is assumed to describe the expansion of the universe. However, by examining empty space with a positive cosmological constant (i.e., a de Sitter space), we find that this assumption is…

General Physics · Physics 2025-08-05 J. M. Greben

The $f(R)$ gravity can be cast into the form of a scalar-tensor theory, and scalar degree of freedom can be suppressed in high-density regions by the chameleon mechanism. In this article, for the general $f(R)$ gravity, using a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-04 Tan Liu , Xing Zhang , Wen Zhao

We study a cosmological setup consisting of a FRW metric as the background geometry with a massless scalar field in the framework of classical polymerization of a given dynamical system. To do this, we first introduce the polymeric…

General Relativity and Quantum Cosmology · Physics 2014-10-21 B. Vakili , K. Nozari , V. Hosseinzadeh , M. A. Gorji
‹ Prev 1 2 3 10 Next ›