English
Related papers

Related papers: Anistropic Invariant FRW Cosmology

200 papers

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

We study teleparallel gravitational theories with are invariant under the conformal transformations. Wide family of the gravitational Lagrangians that are invariant under conformal transformations have investigated. Cosmological solutions…

General Relativity and Quantum Cosmology · Physics 2014-06-24 Davood Momeni , Ratbay Myrzakulov

The quantization of the Friedmann-Robertson-Walker spacetime in the presence of a negative cosmological constant was used in a recent paper to conclude that there are solutions that avoid singularities (big bang--big crunch) at the quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Paolo Amore , Alfredo Aranda , Mayra Cervantes , J. L. Díaz-Cruz , Francisco M. Fernández

In this paper, we analyze the dynamics of an isotropic closed Universe in the presence of a cosmological constant term and we compare its behavior in the standard Wheeler-DeWitt equation approach with the one when a Lagrangian fluid is…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Andrea Campolongo , Giovanni Montani

A generalized model of space-time is given, taking into consideration the anisotropic structure of fields which are depended on the position and the direction (velocity).In this framework a generalized FRW-metric the Raychaudhouri and…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. C. Stavrinos , A. P. Kouretsis , M. Stathakopoulos

We study the effects of an information-theoretically motivated nonlinear correction to the Wheeler-deWitt equation in the minisuperspace scheme for flat, $k=0$, Friedmann-Robertson-Walker (FRW) universes. When the only matter is a…

General Relativity and Quantum Cosmology · Physics 2014-11-18 Le-Huy Nguyen , Rajesh R. Parwani

In this article we perform the Wheeler-DeWitt quantization for Bianchi type $I$ anisotropic cosmological model in the presence of a scalar field minimally coupled to the Einstein-Hilbert gravity theory. We also consider the cosmological…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Saumya Ghosh , Sunandan Gangopadhyay , Prasanta K. Panigrahi

We present a Friedmann-Robertson-Walker (FRW) quantum cosmological model within the framework of Finslerian geometry. In this work, we consider a specific fluid. We obtain the corresponding Wheeler-DeWitt equation as the usual constraint…

General Physics · Physics 2019-11-04 S S De , Farook Rahaman , Nupur Paul

The Universe is homogeneous and isotropic on large scales, so on those scales it is usually modelled as a Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) space-time. The non-linearity of the Einstein field equations raises concern over…

General Relativity and Quantum Cosmology · Physics 2021-03-03 Yonadav Barry Ginat

In the scope of the nonlinear massive gravity, we study fixed points of evolution equations for a Bianchi type--I universe. We find a new attractor solution with non-vanishing anisotropy, on which the physical metric is isotropic but the…

High Energy Physics - Theory · Physics 2012-10-17 A. Emir Gumrukcuoglu , Chunshan Lin , Shinji Mukohyama

We quantize three Friedmann-Robertson-Walker models in the presence of a negative cosmological constant and radiation. The models differ from each other by the constant curvature of the spatial sections, which may be positive, negative or…

General Relativity and Quantum Cosmology · Physics 2009-11-11 G. A. Monerat , E. V. Correa Silva , G. Oliveira-Neto , L. G. Ferreira Filho , N. A. Lemos

We investigate the quantum modified cosmological dynamical equations in a Friedmann-Robertson-Walker universe filled with a barotropic fluid and a general non-canonical scalar field characterized by a Lagrangian similar to k-essence model…

General Relativity and Quantum Cosmology · Physics 2024-03-06 Rituparna Mandal , Soma Sanyal

We analyze the possibility of global anisotropy of the universe. We consider an altered Friedmann Lemaitre Robertson Walker metric in which there are different scale factors along the three different axes of space. We construct the…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-06 Mark P. Hertzberg , Abraham Loeb

This article deals with a nonrelativistic cosmological model based on Galilean covariance, formulated within a five-dimensional Galilean manifold. Within this framework, we construct an isotropic and homogeneous metric analogous to the…

General Relativity and Quantum Cosmology · Physics 2025-11-17 R. G. G. Amorim , A. F. Santos , K. V. S. Araújo , S. C. Ulhoa

We investigate anisotropic fluid cosmology in a situation where the spacetime metric back-reacts in a local, time-dependent way to the presence of inhomogeneities. We derive exact solutions to the Einstein field equations describing…

General Relativity and Quantum Cosmology · Physics 2021-08-25 Mariano Cadoni , Andrea P. Sanna

The vacuum transition probabilities for anisotropic universes in the presence of a scalar field potential in the Wentzel-Kramers-Brillouin approximation are studied. We follow the work by Cespedes et al [Phys. Rev. D 104, 026013 (2021)],…

High Energy Physics - Theory · Physics 2021-12-01 H. García-Compeán , D. Mata-Pacheco

This paper discusses the problem of inflation in the context of Friedmann-Robertson-Walker Cosmology. We show how, after a simple change of variables, one can quantize the problem in a way which parallels the classical discussion. The…

High Energy Physics - Theory · Physics 2007-05-23 Marvin Weinstein , Ratin Akhoury

We construct cosmological models consisting of large numbers of identical, regularly spaced masses. These models do not rely on any averaging procedures, or on the existence of a global Friedmann-Robertson-Walker (FRW) background. They are…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Timothy Clifton

We study the static cosmological solutions and their stability at background level in the framework of massive bigravity theory with Friedmann-Robertson-Walker (FRW) metrics. By the modification proposed in the cosmological equations…

General Relativity and Quantum Cosmology · Physics 2017-05-17 M. Mousavi , F. Darabi

We consider the general scalar field Horndeski Lagrangian coupled to matter. Within this class of models, we present two results that are independent of the particular form of the model. First, we show that in a Friedmann-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2016-02-24 Adalto R. Gomes , Luca Amendola
‹ Prev 1 2 3 10 Next ›