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Related papers: Fractional Einstein-Gauss-Bonnet scalar field cosm…

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In this work we present the late-time behaviour of the Universe in the context of Einstein-Gauss-Bonnet gravitational theory. The theory involves a scalar field, which represents low-effective quantum corrections, assisted by a function…

General Relativity and Quantum Cosmology · Physics 2022-04-19 S. A. Venikoudis , K. V. Fasoulakos , F. P. Fronimos

We study the dynamics of the field equations in a five-dimensional spatially flat Friedmann-Lema\^itre-Robertson-Walker metric in the context of a Gauss-Bonnet-Scalar field theory where the quintessence scalar field is coupled to the…

General Relativity and Quantum Cosmology · Physics 2024-07-29 Alfredo D. Millano , Claudio Michea , Genly Leon , Andronikos Paliathanasis

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

We study the dynamics of the field equations in a four-dimensional isotropic and homogeneous spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker geometry in the context of Einstein-Gauss-Bonnet theory with a matter source and a…

General Relativity and Quantum Cosmology · Physics 2023-08-02 Alfredo D. Millano , Genly Leon , Andronikos Paliathanasis

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

Theoretical arguments and cosmological observations suggest that Einstein's theory of general relativity needs to be modified at high energies. One of the best motivated higher-curvature extensions of general relativity is…

General Relativity and Quantum Cosmology · Physics 2017-08-04 Laura Sberna

The influence of non-minimal coupling of a scalar field and the Gauss-Bonnet term on the inflationary stage of evolution of the universe is investigated in this paper. The main cosmological effects of such a coupling were considered. The…

General Relativity and Quantum Cosmology · Physics 2020-12-30 Igor Fomin

We perform a detailed study of the phase-space of the field equations of an Einstein-Gauss-Bonnet scalar field cosmology for a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime. For the scalar field potential, we consider…

General Relativity and Quantum Cosmology · Physics 2023-02-21 Alfredo D. Millano , Genly Leon , Andronikos Paliathanasis

We consider a physically viable cosmological model that has a field dependent Gauss-Bonnet coupling in its effective action, in addition to a standard scalar field potential. The presence of such terms in the four dimensional effective…

High Energy Physics - Theory · Physics 2008-11-26 Ishwaree P Neupane , Benedict M N Carter

Recently, the research community has been exploring fractional calculus to address problems related to cosmology; in this approach, the gravitational action integral is altered, leading to a modified Friedmann equation, then the resulting…

General Relativity and Quantum Cosmology · Physics 2023-02-07 Bayron Micolta-Riascos , Alfredo D. Millano , Genly Leon , Cristián Erices , Andronikos Paliathanasis

In this work by using a numerical analysis, we investigate in a quantitative way the late-time dynamics of scalar coupled $f(R,\mathcal{G})$ gravity. Particularly, we consider a Gauss-Bonnet term coupled to the scalar field coupling…

General Relativity and Quantum Cosmology · Physics 2022-07-27 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos

We propose a new type of cosmological model derived from the fractional variational principle when it is applied to the gravitational sector of action functional. In contrast to the fractional cosmological model developed earlier by the…

General Relativity and Quantum Cosmology · Physics 2013-04-30 V. K. Shchigolev

We consider cosmological constraints arising from the background expansion history on the ef- fective field theory of cosmic acceleration, a theoretical framework that allows for a unified way to classify both models of dark energy and…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-10 Eva-Maria Mueller , Rachel Bean , Scott Watson

Recently, a new field of study called fractional cosmology has emerged. It uses fractional calculus to modify the standard derivative equations and change the Friedmann equations. The evolution of cosmic species densities is also affected…

General Relativity and Quantum Cosmology · Physics 2023-05-01 Genly Leon , Miguel A. García-Aspeitia , Guillermo Fernandez-Anaya , Alberto Hernández-Almada , Juan Magaña , Esteban González

In this paper, we consider a gravitational action containing a combination of the Ricci scalar, $R$, and the topological Gauss--Bonnet term, $G$. Specifically, we study the cosmological features of a particular class of modified gravity…

General Relativity and Quantum Cosmology · Physics 2023-03-15 Francesco Bajardi , Rocco D'Agostino

Considering the Friedmann--Lema\^{i}tre--Robertson--Walker (FLRW) metric and the Einstein scalar field system as an underlying gravitational model to construct fractional cosmological models has interesting implications in both classical…

General Relativity and Quantum Cosmology · Physics 2024-07-26 S. M. M. Rasouli , S. Cheraghchi , P. V. Moniz

In this work, we analyze the Einstein-scalar-Gauss-Bonnet (EsGB) theory of gravity in a cosmological context using the formalism of dynamical systems. We obtain the equations of motion of the theory and introduce an appropriate set of…

General Relativity and Quantum Cosmology · Physics 2025-09-23 Miguel A. S. Pinto , João Luís Rosa

Several models within the framework of Einstein-Gauss-Bonnet gravities are considered with regard their late-time phenomenological viability. The models contain a non-minimally coupled scalar field and satisfy a constraint on the scalar…

General Relativity and Quantum Cosmology · Physics 2025-03-25 S. D. Odintsov , V. K. Oikonomou , German S. Sharov

We explore a cosmological framework in which a Gauss-Bonnet (GB) coupled scalar field, acting as dark energy, interacts with a fermionic dark matter field through a coupling obtained from the point of view of particle physics. This setup is…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-06 Simran Arora , Saddam Hussain , Benjamin Rose , Anzhong Wang

Dark energy cosmologies with an equation of state parameter $w$ less than -1 are often found to violate the null energy condition and show unstable behaviour. A solution to this problem may require the existence of a consistent effective…

High Energy Physics - Theory · Physics 2009-04-22 Ben M. Leith , Ishwaree P. Neupane
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