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Related papers: Cosmic Acceleration and Anisotropic models with Ma…

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When recent observational evidence and the GR+FRW+CDM model are combined we obtain the result that the Universe is accelerating, where the acceleration is due to some not-yet-understood "dark sector". There has been a considerable number of…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-17 Jonathan A. Pearson

In this paper we have studied the dynamics of accelerating scenario within the framework of scalar field models possessing a non-canonical kinetic term. In this toy model, the scalar field is allowed to interact with the dark matter…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Sudipta Das , Abdulla Al Mamon

This paper consider an universe dominated by baryonic matter, radiation and a nonminimally coupled massive scalar field under the action of a symmetry breaking potential. Inflation occurs naturally with appropriated slow-roll values. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-02 S. H. Pereira

We propose a new scenario for the onset of positive acceleration of our Universe based on symmetry breaking in coupled dark energy scalar field model. In a symmetry breaking process where the scalar field rolls down its own potential, the…

General Relativity and Quantum Cosmology · Physics 2016-10-11 H. Mohseni Sadjadi , M. Honardoost , H. R. Sepangi

We investigate anisotropic and homogeneous cosmological models in the scalar-tensor theory of gravity with non-minimal kinetic coupling of a scalar field to the curvature given by the function $\eta\cdot(\phi/2)\cdot G_{\mu\nu}\,\nabla^\mu…

General Relativity and Quantum Cosmology · Physics 2025-05-13 Ruslan K. Muharlyamov , Tatiana N. Pankratyeva , Shehabaldeen O. A. Bashir

Magnetic fields are observed not only in stars, but in galaxies, clusters, and even high redshift Lyman-alpha systems. In principle, these fields could play an important role in structure formation and also affect the anisotropies in the…

Astrophysics · Physics 2009-10-31 Roy Maartens

Cosmological scaling solutions, which give rise to a scalar-field density proportional to a background fluid density during radiation and matter eras, are attractive to alleviate the energy scale problem of dark energy. In the presence of…

General Relativity and Quantum Cosmology · Physics 2010-03-25 Junko Ohashi , Shinji Tsujikawa

We study the cosmological evolution for a universe in the presence of a continuous tower of massive scalar fields which can drive the current phase of accelerated expansion of the universe and, in addition, can contribute as a dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jose Beltrán Jiménez , David F. Mota , Paulo Santos

Below scales of about 100/h Mpc our universe displays a complex inhomogeneous structure dominated by voids, with clusters of galaxies in sheets and filaments. The coincidence that cosmic expansion appears to start accelerating at the epoch…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 David L. Wiltshire

This article looks at how inhomogeneous spacetime models may be significant for cosmology. First it looks at how the averaging process may affect large scale dynamics, with backreaction effects leading to effective contributions to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 George F R Ellis

A large class of $\Lambda < 0$ cosmologies have big-bang / big crunch spacetimes with time-symmetric backgrounds and asymptotically AdS Euclidean continuations suggesting a possible holographic realization. We argue that these models…

High Energy Physics - Theory · Physics 2023-06-14 Stefano Antonini , Petar Simidzija , Brian Swingle , Mark Van Raamsdonk , Chris Waddell

In this paper, we study a triad of inhomogeneous scalar fields, known as "solid", as a source of homogeneous but anisotropic dark energy. By using a dynamical system approach, we find that anisotropic accelerated solutions can be realized…

General Relativity and Quantum Cosmology · Physics 2021-04-22 J. Motoa-Manzano , J. Bayron Orjuela-Quintana , Thiago S. Pereira , César A. Valenzuela-Toledo

Is it possible that the current cosmic accelerating expansion will turn into a decelerating one? Can this transition be realized by some viable theoretical model that is consistent with the standard Big Bang cosmology? We study a class of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Tianlong Zu , Jiewen Chen , Yang Zhang

In the present work, we execute the Lie symmetry analysis on the Einstein-Maxwell field equations in the plane symmetric spacetime. Under the background of the plane symmetric space-time we compute the Lie point symmetries, perform the…

General Physics · Physics 2020-06-16 Anil Kumar Yadav , Ahmad T. Ali , Saibal Ray , F. Rahaman , A. Mallick

The possibility of explanation of accelerated expansion of the Universe by tachyonic scalar fields which homogeneously fill the world is discussed. The dependences of potential and kinetic term on scale factor are deduced for the case of…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-14 Bohdan Novosyadlyj

In the timescape scenario cosmic acceleration is understand as an apparent effect, due to gravitational energy gradients that grow when spatial curvature gradients become significant with the nonlinear growth of cosmic structure. This…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-14 David L. Wiltshire

Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincar\'e gauge theory of gravity. It is shown that by certain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. V. Minkevich , A. S. Garkun , V. I. Kudin

We review recent results on the cosmological models based on the holographic principle which were proposed to explain the most of the problems occurring in the Standard Cosmological Model. It is shown that these models naturally solve the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Yu. L. Bolotin , O. A. Lemets , D. A. Yerokhin , L. G. Zazunov

The current accelerating phase of the evolution of the universe is considered by constructing most economical cosmic models that use just general relativity and some dominating quantum effects associated with the probabilistic description…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pedro F. González-Díaz , Alberto Rozas-Fernández

Quintessence theories for cosmic acceleration imbue dark energy with a non-trivial dynamics that offers hope in distinguishing the physical origin of the component. We review quintessence models with an emphasis on this dynamics and discuss…

Astrophysics · Physics 2009-06-23 Eric V. Linder