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We investigate the dynamical properties of a class of spatially homogeneous and isotropic cosmological models containing a barotropic perfect fluid and multiple scalar fields with independent exponential potentials. We show that the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. A. Coley , R. J. van den Hoogen

A special class of conformal gravity theories is proposed to solve the long standing problem of the fine-tuned cosmological constant. In the proposed model time evolution of the inflaton field leaves behind a nearly vanishing, but finite…

High Energy Physics - Phenomenology · Physics 2022-04-25 M. Yoshimura

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

A mathematical model of the Universe evolution, based on asymmetric doublet of classical and phantom dcalar Higgs fields with a kinetic connection between the components, has been constructed and studied. A detailed qualitative analysis was…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Yu. G. Ignat'ev , I. A. Kokh

Self-similar, spherically symmetric cosmological models with a perfect fluid and a scalar field with an exponential potential are investigated. New variables are defined which lead to a compact state space, and dynamical systems methods are…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Alan Coley , Martin Goliath

This paper invokes a new mechanism for reducing a coupled system of fields (including Einstein's equations without a cosmological constant) to equations that possess solutions exhibiting characteristics of immediate relevance to current…

General Relativity and Quantum Cosmology · Physics 2019-11-05 Robin W. Tucker , Timothy J. Walton , Manuel Arrayás , José L. Trueba

Several isotropic, homogeneous cosmological models containing a self-interacting minimally coupled scalar field, a perfect fluid source and cosmological constant are solved. New exact, asymptotically stable solutions with an inflationary…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Luis P. Chimento , Alejandro S. Jakubi

Starting from pure multidimensional gravity with curvature-nonlinear terms but no matter fields in the initial action, we obtain a cosmological model with two effective scalar fields related to the size of two extra factor spaces. The model…

General Relativity and Quantum Cosmology · Physics 2010-04-21 K. A. Bronnikov , S. G. Rubin , I. V. Svadkovsky

We use phase space methods to investigate closed, flat, and open Friedmann-Robertson-Walker cosmologies with a scalar potential given by the sum of two exponential terms. The form of the potential is motivated by the dimensional reduction…

High Energy Physics - Theory · Physics 2009-11-10 Laur Jarv , Thomas Mohaupt , Frank Saueressig

A 5-dimensional cosmological solution in the model with two 2-forms and two ``phantom'' scalar fields is considered. The model contains two dilatonic coupling vectors obeying certain restrictions. It is shown that there exists a time…

General Relativity and Quantum Cosmology · Physics 2008-04-17 S. B. Fadeev , V. D. Ivashchuk

In this letter we investigate acceleration in the flat cosmological model with a conformally coupled phantom field and we show that acceleration is its generic feature. We reduce the dynamics of the model to a 3-dimensional dynamical system…

High Energy Physics - Theory · Physics 2008-11-26 Orest Hrycyna , Marek Szydlowski

In this work, we present two brane-world-type solutions in a two-dimensional (2D) dilaton gravity model with singular space-time backgrounds. By employing a first-order superpotential formalism, we first construct the 2D analogues of the…

High Energy Physics - Theory · Physics 2025-11-11 Peng Yu , Yuan Zhong , Ziqi Wang , Hui Wang , Mengyang Zhang

We find new solutions to the five-dimensional Einstein-Maxwell-dilaton theory with cosmological constant where the dilaton field couples to the electromagnetic field as well as to the cosmological term with two different coupling constants.…

General Relativity and Quantum Cosmology · Physics 2018-08-14 A. M. Ghezelbash

We study cosmological inflation in the Einstein gravity model, where additionally the Gauss-Bonnet term non-minimally coupled to a scalar field is included. We prove that inflationary solutions of exponential and power-law types are…

General Relativity and Quantum Cosmology · Physics 2017-12-06 Igor V. Fomin , Sergey V. Chervon

In this paper we analyze the asymptotic behavior of Cardassian cosmological models filled with a perfect fluid and a scalar field with an exponential potential. Cardassian cosmologies arise from modifications of the Friedmann equation, and…

Astrophysics · Physics 2016-08-30 Ruth Lazkoz , Genly Leon

We obtain exact solutions for the Einstein equations with an exponential-potential scalar field (\(V=\Lambda e^{k\phi}\)) which represent simple inhomogeneous generalizations of Bianchi I cosmologies. Studying these equations numerically we…

General Relativity and Quantum Cosmology · Physics 2010-11-01 J. M. Aguirregabiria , A. Feinstein , J. Ibanez

We consider a $(4 + 2k)$ - dimensional Einstein-Gauss-Bonnet model with the cosmological $\Lambda$-term. Exact stable solutions with three constant Hubble-like parameters in this model are obtained. In this case, the multidimensional…

General Relativity and Quantum Cosmology · Physics 2020-01-29 K. K. Ernazarov

We study dynamics of induced gravity cosmological models with sixth degree potential, that have found using the superpotential method. The important property of these models are existence of exact cosmological solutions that tend to fixed…

General Relativity and Quantum Cosmology · Physics 2014-07-29 Ekaterina O. Pozdeeva , Sergey Yu. Vernov

In this paper, we discuss the dynamics of two- scalar-field cosmological models. Unlike in the situation of exponential potential, we find that there are late-time attractors in which one scalar field dominates the energy density of…

General Relativity and Quantum Cosmology · Physics 2017-11-09 Yu Li

We develop a bifurcation-theoretic description of Friedmann--Robertson--Walker cosmologies with a scalar field $\phi$, a barotropic fluid of index $\gamma$, and spatial curvature. For the strict exponential potential…

General Relativity and Quantum Cosmology · Physics 2026-04-08 Spiros Cotsakis