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相关论文: The simplest parametrization of equation of state …

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In the paper, we present an accelerating cosmological model in $f(R,\mathcal{L}_{m})$ gravity with the parameter constrained through the cosmological data sets. At the beginning, we have employed a functional form of $f(R,\mathcal{L}_{m})…

广义相对论与量子宇宙学 · 物理学 2025-01-10 Y. Kalpana Devi , S. A. Narawade , B. Mishra

In this paper, we have proposed a model of accelerating Universe with binary mixture of bulk viscous fluid and dark energy. and probed the model parameters: present values of Hubble's constant $H_{0}$, Equation of state paper of dark energy…

广义相对论与量子宇宙学 · 物理学 2021-08-18 Nishant Singla , M. K. Gupta , Anil Kumar Yadav , G. K. Goswami

In this article, we introduce an innovative parametric representation of the Hubble parameter, providing a model-independent means to explore the dynamics of an accelerating cosmos. The model's parameters are rigorously constrained through…

宇宙学与河外天体物理 · 物理学 2024-04-16 M. Koussour , N. Myrzakulov , M. K. M. Ali

We present a new $f(Q)$ cosmological model capable of reproducing late-time acceleration, i.e. $f\left( Q\right) = \lambda_{0}\left( \lambda +Q\right) ^{n}$ by supporting certain parametrization of the Hubble parameter. By using…

广义相对论与量子宇宙学 · 物理学 2023-06-26 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

We study the late-time cosmology in $f(R, G)=R+\alpha R^{2}+\beta e^{\gamma G}$, using a logarithmic parametrization of the deceleration parameter $q(z)=q_{0}+q_{1}sin[log(1+z)]$. The Hubble parameter $H(z)$ is reconstructed and model…

广义相对论与量子宇宙学 · 物理学 2025-06-10 Amit Samaddar , S. Surendra Singh

In this study, we have explored a scalar field cosmological model in the axially symmetric Bianchi type-I universe. In this study, our aim is to constrain the scalar field dark energy model in an anisotropic background. For this purpose,…

广义相对论与量子宇宙学 · 物理学 2025-11-19 Vinod Kumar Bhardwaj , Anil Kumar Yadav

This study proposes a novel parametrization approach for the dimensionless Hubble parameter i.e. $E^2(z)=A(z)+\beta (1+\gamma B(z))$ in the context of scalar field dark energy models. The parameterization is characterized by two functions,…

宇宙学与河外天体物理 · 物理学 2023-11-09 M. Koussour , N. Myrzakulov , S. Myrzakulova , D. Sofuoğlu

In this paper, we have investigated a bulk viscous anisotropic Universe and constrained its model parameters with recent $H(z)$ and Pantheon compilation data. Using cosmic chronometric technique, we estimate the present value of Hubble's…

广义相对论与量子宇宙学 · 物理学 2021-06-10 G. K. Goswami , Anil Kumar Yadav , B. Mishra , S. K. Tripathy

In this paper, the cosmological model of the Universe has been presented in $f(Q)$ gravity and the parameters are constrained from the cosmological data sets. At the beginning, we have employed a well motivated form of $f(Q) = \alpha +…

广义相对论与量子宇宙学 · 物理学 2023-06-01 S. A. Narawade , B. Mishra

The dynamics of the Universe is analyzed using an exponential function for the dark energy equation of state, known as Gong-Zhang parameterization. The phase space of the free parameters presented in the model is constrained using Cosmic…

宇宙学与河外天体物理 · 物理学 2023-04-19 Mónica N. Castillo-Santos , A. Hernández-Almada , Miguel A. García-Aspeitia , Juan Magaña

This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…

广义相对论与量子宇宙学 · 物理学 2022-08-23 S. K. J. Pacif , Simran Arora , P. K. Sahoo

In this paper, we focus on the parametrization of the effective equation of state (EoS) parameter within the framework of $f(Q)$ symmetric teleparallel gravity. Here, the gravitational action is represented by an arbitrary function of the…

广义相对论与量子宇宙学 · 物理学 2023-07-04 A. Mussatayeva , N. Myrzakulov , M. Koussour

In this paper, we have investigated late time acceleration for a spatially flat dust filled Universe in Brans-Dicke theory in the presence of a positive cosmological constant $\Lambda$ . Expressions for Hubble's constant, luminosity…

广义相对论与量子宇宙学 · 物理学 2017-10-23 G. K. Goswami

We propose a novel dark-energy equation-of-state parametrization, with a single parameter $\eta$ that quantifies the deviation from $\Lambda$CDM cosmology. We first confront the scenario with various datasets, from Hubble function (OHD),…

广义相对论与量子宇宙学 · 物理学 2024-06-04 J. K. Singh , Preeti Singh , Emmanuel N. Saridakis , Shynaray Myrzakul , Harshna Balhara

In this paper, we have considered a spatially flat FRW universe filled with pressureless matter and dark energy. We have considered a phenomenological parametrization of the deceleration parameter $q(z)$ and from this we have reconstructed…

广义相对论与量子宇宙学 · 物理学 2017-03-22 Abdulla Al Mamon , Sudipta Das

A new parametrization of the Hubble parameter is proposed to explore the issue of the cosmological landscape. The constraints on model parameters are derived through the Markov Chain Monte Carlo (MCMC) method by employing a comprehensive…

宇宙学与河外天体物理 · 物理学 2024-05-06 L. Sudharani , Kazuharu Bamba , N. S. Kavya , V. Venkatesha

In this paper we investigate an observable universe in Bianchi type V space-time by taking into account the cosmological constant as the source of energy. We have performed a $\chi^{2}$ test to obtain the best fit values of the model…

综合物理 · 物理学 2021-03-23 Rajendra Prasad , Manvinder Singh , Anil Kumar Yadav , A. Beesham

We present a model for the present accelerating Universe and focus on the different important physical variables involved in the model under the phenomenological assumption $\Lambda \propto H^2$ with a prescription for equation of state…

综合物理 · 物理学 2011-07-15 Saibal Ray , Farook Rahaman , Utpal Mukhopadhyay , Ruby Sarkar

In this work, we have proposed a general dark energy density parametrization to study the evolution of the universe. We have also constrained the model parameters using the combination of Type Ia supernova (SNIa), baryonic acoustic…

广义相对论与量子宇宙学 · 物理学 2018-07-25 Abdulla Al Mamon

In this paper, we investigate a scalar field Brans-Dicke cosmological model in Lyra's geometry which is based on the modifications in geometrical term as well as energy term of Einstein's field equations. We have examined the validity of…

广义相对论与量子宇宙学 · 物理学 2023-11-15 Rajendra Prasad , Lalit Kumar Gupta , Anil Kumar Yadav
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