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In this article, we propose an anisotropic Bianchi-I type cosmological model in non-conservative Unimodular Gravity ($\mathrm{NUG}$). We show that simply using the Bianchi-I type metric does not resolve a striking characteristic of the…

General Relativity and Quantum Cosmology · Physics 2025-11-26 Marcelo H. Alvarenga , Júlio C. Fabris

The canonical quantum theory of gravity -- Quantum Geometrodynamics (QG) is applied to the homogeneous Bianchi type IX cosmological model. As a result, the framework for the quantum theory of homogeneous cosmologies is developed. We show…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Arkady Kheyfets , Warner A. Miller , Ruslan Vaulin

Recently a Born-Infeld action for dark energy and dark matter that uses additional affine connections was proposed. At background level, it was shown that the new proposal can mimic the standard cosmological evolution. In Bianchi…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Davi C. Rodrigues

Considering the Universe as a dynamic system, the understanding of its evolution is an interesting aspect of study in cosmology. Here, we investigate the anisotropic locally rotationally symmetric (LRS) Bianchi type-I (LRS-BI) spacetime…

General Relativity and Quantum Cosmology · Physics 2024-06-21 Pranjal Sarmah , Umananda Dev Goswami

We present a reconstruction algorithm for cosmological models based on $f(\mathcal{Q})$ gravity. We specifically focus on obtaining exact Bianchi Type-I and Friedmann-Lema\^{\i}tre-Robertson-Walker solutions, finding solutions that might…

General Relativity and Quantum Cosmology · Physics 2022-05-12 Fabrizio Esposito , Sante Carloni , Roberto Cianci , Stefano Vignolo

In the isotropic quantum cosmological perfect fluid model, the initial singularity can be avoided, while the classical behaviour is recovered asymptotically. We verify if initial anisotropies can also be suppressed in a quantum version of a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 F. G. Alvarenga , A. B. Batista , J. C. Fabris , S. V. B. Goncalves

The behaviour of the flat anisotropic model of the Universe with a scalar field is explored within the framework of quantum cosmology. The principal moment of the account of an anisotropy is the presence either negative potential barrier or…

General Relativity and Quantum Cosmology · Physics 2015-06-25 V. N. Folomeev , V. Ts. Gurovich

The exact renormalization group flow equations for gravity lead to quantum corrections of Newton's constant and cosmological constant. Using this we investigate the Bianchi-I cosmological model at late times. In particular, we obtain the…

General Relativity and Quantum Cosmology · Physics 2022-08-11 Sunandan Gangopadhyay , Rituparna Mandal , Amitabha Lahiri

A model for an anisotropic Bianchi type VI universe in a Scale Covariant theory of gravitation (Canuto et al. 1977) is analyzed. A finite singularity is found in the model at the initial time $t=0$. All the physical parameters are studied…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Mohd. Zeyauddin , Bijan Saha

Among the general class of metric-affine theories of gravity, there is a special class conformed by those endowed with a projective symmetry. Perhaps the simplest manner to realise this symmetry is by constructing the action in terms of the…

General Relativity and Quantum Cosmology · Physics 2021-04-23 Jose Beltrán Jiménez , Daniel de Andrés , Adrià Delhom

Anisotropic cosmological models are constructed in $f(R,T)$ gravity theory to investigate the dynamics of universe concerning the late time cosmic acceleration. Using a more general and simple approach, the effect of the coupling constant…

General Physics · Physics 2018-10-05 B. Mishra , Sankarsan Tarai , S. K. Tripathy

We consider Bianchi VI spacetime, which also can be reduced to Bianchi types VI0-V-III-I. We initially consider the most general form of the energy-momentum tensor which yields anisotropic stress and heat flow. We then derive an…

General Relativity and Quantum Cosmology · Physics 2011-08-26 Ozgur Akarsu , Can B. Kilinc

This paper is devoted to investigate the anisotropic locally rotationally symmetric (LRS) Bianchi type-I space-time in the context of the recently proposed $f(Q)$ gravity in which $Q$ is the non-metricity scalar. For this purpose, we…

General Relativity and Quantum Cosmology · Physics 2022-08-26 M. Koussour , K. El Bourakadi , S. H. Shekh , S. K. J. Pacif , M. Bennai

In this article, we have discussed the results of our investigation. We consider an anisotropic viscous cosmological model of (LRS) Bianchi type I spacetime universe filled with a viscous fluid under $f(Q)$ gravity. We have studied the…

General Relativity and Quantum Cosmology · Physics 2024-08-14 Anirudh Pradhan , Archana Dixit , Dinesh Chandra Maurya

We investigate quantum cosmological models in an n-dimensional anisotropic universe in the presence of a massless scalar field. Our basic inspiration comes from Chodos and Detweiler's classical model which predicts an interesting behaviour…

General Relativity and Quantum Cosmology · Physics 2018-02-14 F. A. P. Alves-Júnior , M. L. Pucheu , A. B. Barreto , C. Romero

General theory of relativity can be equivalently formulated on a flat space-time associating a torsion-free affine connection of non-vanishing non-metricity scalar $Q$. In this paper, we present an extension of this, viz., the $f(Q)$ theory…

General Relativity and Quantum Cosmology · Physics 2024-11-04 Avik De , Dalia Saha , Ganesh Subramaniam , Abhik Kumar Sanyal

We investigate the classical and quantum behavior of a Bianchi I model in the presence of a stiff matter contribution when the Vilenkin interpretation of the wave function of the Universe is taken into account. We study its evolution in the…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Riccardo Moriconi , Giovanni Montani

In this paper, we consider spatially homogenous and anisotropic Bianchi type I universe in the context of F(T) gravity. We construct some corresponding models using conservation equation and equation of state parameter representing…

General Relativity and Quantum Cosmology · Physics 2015-05-28 M. Sharif , Shamaila Rani

We study the behaviour of Bianchi class A universes containing an ultra-stiff isotropic ghost field and a fluid with anisotropic pressures which is also ultra-stiff on the average. This allows us to investigate whether cyclic universe…

General Relativity and Quantum Cosmology · Physics 2016-05-25 John D. Barrow , Chandrima Ganguly

Contrary to the general belief, there has recently been quite a few examples of unitary evolution of quantum cosmological models. The present work gives more examples, namely Bianchi type VI and type II. These examples are important as they…

General Relativity and Quantum Cosmology · Physics 2016-11-03 Sachin Pandey , Narayan Banerjee