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Related papers: Fractional Scalar Field Cosmology

200 papers

We investigate some FLRW cosmological models in the context of Metric-Affine $F(R,Q)$ gravity, as proposed in [arXiv:1205.52666]. Here, $R$ and $Q$ are the curvature and nonmetricity scalars using non-special connections, respectively. We…

General Relativity and Quantum Cosmology · Physics 2024-08-16 Dinesh Chandra Maurya , K. Yesmakhanova , R. Myrzakulov , G. Nugmanova

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational…

General Relativity and Quantum Cosmology · Physics 2012-02-06 Pankaj Jain , Purnendu Karmakar , Subhadip Mitra , Sukanta Panda , Naveen K. Singh

Fractional differential calculus is a mathematical tool that has found applications in the study of social and physical behaviors considered ``anomalous''. It is often used when traditional integer derivatives models fail to represent cases…

General Relativity and Quantum Cosmology · Physics 2024-05-07 Kevin Marroquín , Genly Leon , Alfredo D. Millano , Claudio Michea , Andronikos Paliathanasis

A scalar-tensor bimetric gravity model of early universe cosmology is reviewed. The metric frame with a variable speed of light (VSL) and a constant speed of gravitational waves is used to describe a Friedmann-Robertson-Walker universe. The…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. W. Moffat

The fractal cosmological model which accounts for observable fractal properties of the Universe's large-scale structure is constructed. In this framework these properties are consequences of the rotary symmetry of charged scalar meson…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-03 I. K. Rozgacheva , A. A. Agapov

A simple algebraic method to obtain exact solutions to the scalar field equations in spatially flat FRW cosmology is derived. The field potential fuction is reduced to two terms which can be used to determine some characteristic…

General Relativity and Quantum Cosmology · Physics 2008-06-16 Marco A. Reyes

A Friedman cosmology is investigated based on scalar-tensor gravitation with general metric coupling and scalar potential functions. We show that for a broad class of such functions, the scalar field can be dynamically trapped using a…

General Relativity and Quantum Cosmology · Physics 2016-10-05 C. H. -T. Wang , J. A. Reid , A. St J. Murphy , D. Rodrigues , M. Al Alawi , R. Bingham , J. T. Mendonca , T. B. Davies

In loop quantum cosmology, Friedmann-LeMaitre-Robertson-Walker (FLRW) space-times arise as well-defined approximations to specific \emph{quantum} geometries. We initiate the development of a quantum theory of test scalar fields on these…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Abhay Ashtekar , Wojciech Kaminski , Jerzy Lewandowski

We investigate the interaction between scalar fields and radiation in the framework of warm inflationary models by using the irreversible thermodynamics of open systems with matter creation/annihilation. We consider the scalar fields and…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Tiberiu Harko , Haidar Sheikhahmadi

We propose an Einstein-{\ae}ther scalar-tensor cosmological model. In particular in the scalar-tensor Action Integral we introduce the {\ae}ther field with {\ae}ther coefficients to be functions of the scalar field. This cosmological model…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Andronikos Paliathanasis , Genly Leon

We develop a quantum-cosmological framework in which the inflationary potential emerges from the structure of the wave function of the universe rather than being postulated. Starting from the Wheeler-DeWitt equation for a flat…

General Relativity and Quantum Cosmology · Physics 2025-10-07 Gerasimos Kouniatalis

We examine Friedmann-Robertson-Walker models in three spacetime dimensions. The matter content of the models is composed of a perfect fluid, with a $\gamma$-law equation of state, and a homogeneous scalar field minimally coupled to gravity…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Norman Cruz , Cristian Martinez

Fractional cosmology modifies the standard derivative to Caputo's fractional derivative of order $\mu$, generating changes in General Relativity. Friedmann equations are modified, and the evolution of the species densities depends on $\mu$…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Miguel A. García-Aspeitia , Guillermo Fernandez-Anaya , A. Hernández-Almada , Genly Leon , Juan Magaña

These lectures provide an introductory review of big bang cosmology. I discuss the expanding Friedmann-Robertson-Walker universe, summarizing the observational evidence which has led to its adoption as the `standard' cosmological model and…

Astrophysics · Physics 2016-10-26 Josh Frieman

The present thesis is focused on the study of FLRW cosmology in modified gravities and with scalar fields. The mystery of dark energy has made that the last decade, many efforts in theoretical physics have been focused on the explanation of…

High Energy Physics - Theory · Physics 2011-04-06 Diego Sáez-Gómez

In this paper we find a solution for a quasi-isotropic inflationary Universe which allows to introduce in the problem a certain degree of inhomogeneity. We consider a model which generalize the (flat) FRW one by introducing a first order…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Giovanni Paolo Imponente , Giovanni Montani

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

In the framework of teleparallel gravity, the Friedman-Robertson-Walker cosmological model with scalar tensor theory where scalar field is non-minimally coupled to both the torsion scalar and boundary term is studied. Utilizing the Noether…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Ganim Gecim , Yusuf Kucukakca

A semiclassical cosmological model is considered which consists of a closed Friedmann-Robertson-Walker in the presence of a cosmological constant, which mimics the effect of an inflaton field, and a massless, non-conformally coupled quantum…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Esteban Calzetta , Enric Verdaguer

We consider a polymer quantization of a free massless scalar field in a homogeneous and isotropic cosmological spacetime. This quantization method assumes that field translations are fundamentally discrete, and is related to but distinct…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-27 Golam Mortuza Hossain , Viqar Husain , Sanjeev S. Seahra