中文
相关论文

相关论文: Bianchi type III models with anisotropic dark ener…

200 篇论文

Understanding the early evolution of the universe requires models that incorporate possible quantum and anisotropic effects in its dynamics. In this work, we analyze the dynamical evolution of locally rotationally symmetric anisotropic…

广义相对论与量子宇宙学 · 物理学 2025-10-13 G. Oliveira-Neto , Y. Soncco Apaza

In this work, we will explore the effects of F(R) theories in the classical scheme using the anisotropic Bianchi Type I cosmological model with standard matter employing a barotropic fluid with equation of state $P=\gamma \rho$. In this…

广义相对论与量子宇宙学 · 物理学 2026-04-15 J. Socorro , Juan Luis Pérez , Luis Rey Díaz-Barrón , Abraham Espinoza García , Sinuhé Pérez Payán

The present study deals with spatially homogeneous and anisotropic locally rotationally symmetric (LRS) Bianchi type I cosmological model with dominance of dark energy. To get the deterministic model of Universe, we assume that the shear…

综合物理 · 物理学 2012-01-24 Anil Kumar Yadav , Bijan Saha

In homogeneous and isotropic loop quantum cosmology, gravity can behave repulsively at Planckian energy densities leading to the replacement of the big bang singularity with a big bounce. Yet in any bouncing scenario it is important to…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Dah-Wei Chiou , Kevin Vandersloot

Anisotropic Bianchi type-III cosmology is examined within the framework of f(R,T) gravity, where R denotes the Ricci scalar and T the trace of the energy-momentum tensor. In this work, we investigate the statistical constraints on…

广义相对论与量子宇宙学 · 物理学 2025-12-23 Mayur Mune , Praveen Kumar Dhankar , Safiqul Islam , Behnam Pourhassan , Muhammad Aamir , Faisal Haroon

The present study deals with spatially homogeneous and anisotropic Bianchi-I cosmological model representing massive strings. The energy-momentum tensor, as formulated by Letelier (Phys. Rev. D 28: 2414, 1983) has been used to construct…

综合物理 · 物理学 2014-03-11 Chanchal Chawla , R. K. Mishra , Anirudh Pradhan

We consider an evolution of anisotropic cosmological model on the example of the Bianchi type I homogeneous universe. It is filled by the mixture of matter and dark energy with an arbitrary barotropic equation of state (EoS). The general…

广义相对论与量子宇宙学 · 物理学 2023-06-14 S L Parnovsky

We consider the conformal Einstein equations for polytropic perfect fluid cosmologies which admit an isotropic singularity. For the polytropic index gamma strictly greater than 1 and less than or equal to 2 it is shown that the Cauchy…

广义相对论与量子宇宙学 · 物理学 2009-10-31 K. Anguige , K. P. Tod

We study the homogeneous but anisotropic cosmological models of Bianchi in presence of a massive scalar field using the ADM Hamiltonian formalism. We begin to describe the main steps to find the ADM Hamiltonian of the General Relativity…

广义相对论与量子宇宙学 · 物理学 2014-04-15 Stephane Fay

Cosmological solutions are obtained in an anisotropic Kantowski-Sachs (KS) and Bianchi Type-I universes considering a cosmological constant with Skyrme fluid. Interestingly, the solutions obtained here in both the KS and Bianchi-I…

广义相对论与量子宇宙学 · 物理学 2022-06-09 Rikpratik Sengupta , B C Paul , Prasenjit Pal

In the present work, we study the dynamical evolution of an homogeneous and anisotropic, noncommutative (NC) Bianchi I (BI) model coupled to a radiation perfect fluid. Our first motivation is determining if the present model tends to an…

广义相对论与量子宇宙学 · 物理学 2024-03-07 G. Oliveira-Neto , T. M. Abreu

We investigate the evolution of anisotropies in Bianchi I spacetimes within the framework of the 4D Einstein-Gauss-Bonnet scalar field theory. The field equations are formulated using dimensionless variables, and the asymptotic dynamics are…

广义相对论与量子宇宙学 · 物理学 2026-01-06 Alex Giacomini , Chevara Hansraj , Genly Leon , Andronikos Paliathanasis

We investigate cosmologies where the accelerated expansion of the Universe is driven by a field with an anisotropic equation of state. We model such scenarios within the Bianchi I framework, introducing two skewness parameters to quantify…

天体物理学 · 物理学 2009-06-23 Tomi Koivisto , David F. Mota

In this paper, dark energy models of the universe filled with wet dark fluid are constructed in the framework of LRS Bianchi type-II space-time in General Theory of Relativity. A new equation of state modeled on the equation of state…

综合物理 · 物理学 2017-06-21 Chandra Rekha Mahanta , Azizur Rahman Sheikh

The dynamics of the tilted axisymmetric Bianchi IX cosmological models are explored allowing energy flux in the source fluid. The Einstein equations and the continuity equation are presented treating the equation of state $w$ and the tilt…

宇宙学与河外天体物理 · 物理学 2015-12-30 Peter Sundell , Tomi Koivisto

Following recent considerations of a non-zero value for the vacuum energy density and the realization that a simple Kantowski-Sachs model might fit the classical tests of cosmology, we study the qualitative behavior of three anisotropic and…

天体物理学 · 物理学 2011-04-15 Paulo Aguiar , Paulo Crawford

In this paper, we have investigated Bianchi Type-III Dark Energy Model in f(R,T) theory of gravity proposed by Harko et al. (Phys. Rev. D84 : 024020, 2011). To find a determinate solution of the field equations we have used (i) the fact…

综合物理 · 物理学 2016-01-13 D. R. K. Reddy , G. Ramesh , S. Umadevi

We study the Bianchi-I cosmological model motivated by signals of statistical isotropy violation seen in cosmic microwave background (CMB) observations and others. To that end, we consider various kinds of anisotropic matter that source…

宇宙学与河外天体物理 · 物理学 2025-06-03 Anshul Verma , Sanjeet K. Patel , Pavan K. Aluri , Sukanta Panda , David F. Mota

Anisotropic cloud string cosmological model with Bianchi type I space time is investigated in the context of general relativity. The exact solutions of Einstein field equations are obtained with when the source for energy momentum tensor is…

综合物理 · 物理学 2019-09-26 Kangujam Priyokumar Singh , Meher Daimary

In this paper, aniostropic dark energy cosmological models have been constructed in a Bianchi-V space-time with the energy momentum tensor consisting of two non-interacting fluids namely bulk viscous fluid and dark energy fluid. Two…

广义相对论与量子宇宙学 · 物理学 2018-02-01 B. Mishra , Pratik P. Ray , S. K. J. Pacif