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In this study, we have explored a scalar field cosmological model in the axially symmetric Bianchi type-I universe. In this study, our aim is to constrain the scalar field dark energy model in an anisotropic background. For this purpose,…

General Relativity and Quantum Cosmology · Physics 2025-11-19 Vinod Kumar Bhardwaj , Anil Kumar Yadav

We consider a cosmological model with two scalar fields minimally coupled to gravity which have a mixed kinetic term. Hence, Chiral cosmology is included in our analysis. The coupling function and the potential function, which depend on one…

General Relativity and Quantum Cosmology · Physics 2019-09-04 N. Dimakis , A. Paliathanasis , Petros A. Terzis , T. Christodoulakis

Study the behaviour and the evolution of the cosmological field equations in an homogeneous and anisotropic spacetime with two scalar fields coupled in the kinetic term. Specifically, the kinetic energy for the scalar field Lagrangian is…

General Relativity and Quantum Cosmology · Physics 2021-10-22 A. Giacomini , P. G. L. Leach , G. Leon , A. Paliathanasis

Cosmological models often contain scalar fields, which can acquire global nonzero expectation values that change with the comoving time. Among the possible consequences of these scalar-field backgrounds, an accelerated cosmological…

High Energy Physics - Phenomenology · Physics 2017-08-23 Ralf Lehnert

Motivated by the recent interest in cosmologies arising from energy density modifications to the Friedmann equation, we analyse the scaling behaviour for a broad class of these cosmologies comprised of scalar fields and background…

Astrophysics · Physics 2009-11-10 Edmund J. Copeland , Seung-Joo Lee , James E. Lidsey , Shuntaro Mizuno

We consider the appearance of multiple scalar fields in SFT inspired non-local models with a single scalar field at late times. In this regime all the scalar fields are free. This system minimally coupled to gravity can be analyzed…

High Energy Physics - Theory · Physics 2011-01-24 Federico Galli , Alexey S. Koshelev

Scalar field cosmologies with a generalized harmonic potential and a matter fluid with a barotropic Equation of State (EoS) with barotropic index $\gamma$ for Locally Rotationally Symmetric (LRS) Bianchi III metric and open…

General Relativity and Quantum Cosmology · Physics 2021-06-03 Genly Leon , Esteban González , Samuel Lepe , Claudio Michea , Alfredo D. Millano

We consider cosmological models with an arbitrary number of scalar fields nonminimally coupled to gravity and construct new integrable cosmological models. In the constructed models, the Ricci scalar is an integral of motion irrespectively…

General Relativity and Quantum Cosmology · Physics 2025-05-23 V. R. Ivanov , S. Yu. Vernov

We compute the effective potential for scalar fields in asymptotically safe quantum gravity. A scaling potential and other scaling functions generalize the fixed point values of renormalizable couplings. The scaling potential takes a…

High Energy Physics - Theory · Physics 2020-12-01 C. Wetterich

We consider Friedmann-Lema\^{\i}tre-Robertson-Walker flat cosmological models in the framework of general Jordan frame scalar-tensor theories of gravity with arbitrary coupling function and potential. For the era when the cosmological…

General Relativity and Quantum Cosmology · Physics 2011-01-06 Laur Järv , Piret Kuusk , Margus Saal

Scalar-tensor gravitational theories are important extensions of standard general relativity, which can explain both the initial inflationary evolution, as well as the late accelerating expansion of the Universe. In the present paper we…

General Relativity and Quantum Cosmology · Physics 2017-06-28 J. A. Belinchón , T. Harko , M. K. Mak

Solutions of gravitational equations of gauge theories of gravity in homogeneous isotropic world with massive scalar field are investigated in the case of flat cosmological models. Special attention is dedicated to general behavior of…

Astrophysics · Physics 2009-11-07 G. V. Vereshchagin

This research focuses on scalar field cosmologies with a generalized harmonic potential. Our attention is centred on the anisotropic LRS Bianchi I and III metrics, Bianchi V metrics, and their isotropic limits. We provide a comprehensive…

General Relativity and Quantum Cosmology · Physics 2023-10-16 Alfredo D. Millano , Genly Leon

The asymptotic behavior of the scalar field and its physical meaning are discussed for T=0 and T\neq 0 for the large enough coupling parameter \omega. The special character of the Brans-Dicke theory is also discussed for local and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. Miyazaki

We investigate the phase-space of a flat FRW universe including both a scalar field, $\phi,$ coupled to matter, and radiation. The model is inspired in scalar-tensor theories of gravity, and thus, related with $F(R)$ theories through…

General Relativity and Quantum Cosmology · Physics 2010-09-06 Genly Leon , Pavel Silveira , Carlos R. Fadragas

We study the cosmological evolution of the field equations in the context of Einstein-Aether cosmology by including a scalar field in a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime. Our analysis is separated into two…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Andronikos Paliathanasis , G. Papagiannopoulos , Spyros Basilakos , John D. Barrow

We analyze the quantum supersymmetric cosmological FRW model with a scalar field, with a conditional probability density and the scalar field identified as time. The Hilbert space has a spinorial structure and there is only one consistent…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Ramírez , V. Vázquez-Báez

We explore the dynamical behaviour of cosmological models involving a scalar field (with an exponential potential and a canonical kinetic term) and a matter fluid with spatial curvature included in the equations of motion. Using…

General Relativity and Quantum Cosmology · Physics 2016-10-13 Mateja Gosenca , Peter Coles

We consider the FRW cosmological model in which the matter content of universe (playing a role of inflaton or quintessence) is given by a novel generalization of the massive scalar field. The latter is a scalar version of the recently…

General Relativity and Quantum Cosmology · Physics 2017-09-05 Jakub Mielczarek , Tomasz Trześniewski

The cosmological dynamics of multiple scalar/pseudoscalar fields are difficult to solve, especially when the field-space metric is curved. This presents a challenge in determining whether a given model can support cosmic acceleration,…

High Energy Physics - Theory · Physics 2024-09-23 Gary Shiu , Flavio Tonioni , Hung V. Tran