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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

We propose a novel approach to parameterize the equation of state for Scalar Field Dark Energy (SFDE) and use it to derive analytical solutions for various cosmological parameters. Using statistical MCMC with Bayesian techniques, we obtain…

宇宙学与河外天体物理 · 物理学 2023-11-22 M. Koussour , Y. Sekhmani , Alnadhief H. A. Alfedeel , F. Awad , N. Myrzakulov

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

宇宙学与河外天体物理 · 物理学 2013-09-17 Muhammad Omer Farooq

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, a well-motivated parametrization of the Hubble parameter ($H$% ) is revisited that renders two models of dark energy showing some intriguing features of the late-time accelerating Universe. A general quintessence field is…

广义相对论与量子宇宙学 · 物理学 2023-09-19 Amine Bouali , Himanshu Chaudhary , Amritansh Mehrotra , S. K. J. Pacif

The current paper provides a comprehensive examination of a dark energy cosmological model in the classical regime, in which a generic scalar field is regarded as a dark energy source. Einstein's field equations are solved in model…

广义相对论与量子宇宙学 · 物理学 2022-09-07 Ritika Nagpal , Shibesh Kumar Jas Pacif , Abhishek Parida

Scalar fields aptly describe equation of state of dark energy. The scalar field models were initially proposed to circumvent the fine tuning problem of cosmological constant. However, the model parameters also need a fine tuning of their…

宇宙学与河外天体物理 · 物理学 2018-06-19 Archana Sangwan , Ashutosh Tripathi , H. K. Jassal

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

宇宙学与河外天体物理 · 物理学 2018-09-05 Ivan de Martino

The cosmic acceleration observed in the expansion of the Universe has sparked extensive research into the nature of dark energy, which is known to constitute approximately 70\% of the Universe's energy content. In this study, we explore two…

宇宙学与河外天体物理 · 物理学 2024-02-26 M. Koussour , N. S. Kavya , V. Venkatesha , N. Myrzakulov

We constrain two non-flat time-evolving dark energy cosmological models by using Hubble parameter data, Type Ia supernova apparent magnitude measurements, and baryonic acoustic oscillation peak length scale observations. The inclusion of…

宇宙学与河外天体物理 · 物理学 2017-03-22 Omer Farooq , Data Mania , Bharat Ratra

We investigate the evolution of black hole mass within a cosmological background modeled by a Modified Chaplygin Gas (MCG) under various dark energy equation of state parametrizations, including Linear, Logarithmic, CPL, JBP models. The…

广义相对论与量子宇宙学 · 物理学 2026-01-30 Promila Biswas , Subhajit Pal , Sukanya Dutta , Ritabrata Biswas , Farook Rahaman

The background evolution of an accelerated, dark energy dominated universe is aptly described by non-canonical tachyon scalar field models. The accelerated expansion of the universe is determined by the choice of a suitable scalar field…

广义相对论与量子宇宙学 · 物理学 2019-05-10 Avinash Singh , Archana Sangwan , H. K. Jassal

We investigate whether the current Hubble parameter $H(z)$ measurements could help improve the constraints on dark energy on the basis of the mainstream cosmological probes including the type Ia supernovae (SN) observation, the cosmic…

宇宙学与河外天体物理 · 物理学 2019-05-16 Yan Liu , Rui-Yun Guo , Jing-Fei Zhang , Xin Zhang

We study the observational constraints on the cosmic evolution of the relationships between the massive black hole (MBH) mass (M_bh) and the stellar mass (M^*_sph; or velocity dispersion \sigma) of the host galaxy/spheroid. Assuming that…

宇宙学与河外天体物理 · 物理学 2015-06-11 Xiaoxia Zhang , Youjun Lu , Qingjuan Yu

This paper explores the dark energy phenomenon within the context of $f(R,L_m)$ gravity theory. Two specific non-linear $f (R, L_m)$ models are considered: $f(R,L_m)=\frac{R}{2}+L_m^\alpha$ and $f(R,L_m)=\frac{R}{2}+(1+\alpha R)L_m$, where…

宇宙学与河外天体物理 · 物理学 2023-12-13 S. Myrzakulova , M. Koussour , N. Myrzakulov

Knowing the late time evolution of the Universe and finding out the causes for this evolution are the important challenges of modern cosmology. In this work, we adopt a model-independent cosmographic approach and approximate the Hubble…

宇宙学与河外天体物理 · 物理学 2019-01-23 Salvatore Capozziello , Ruchika , Anjan A Sen

The evolution of the mass of a black hole embedded in a universe filled with dark energy and cold dark matter is calculated in a closed form within a test fluid model in a Schwarzschild metric, taking into account the cosmological evolution…

广义相对论与量子宇宙学 · 物理学 2014-11-21 J. A. S. Lima , Daniel C. Guariento , J. E. Horvath

In this work we perform some studies related to dark energy. Firstly, we propose a dynamical approach to explain the dark energy content of the universe. We assume that a massless scalar field couples to the Hubble parameter with some…

高能物理 - 唯象学 · 物理学 2009-01-07 Fei Wang , Jin Min Yang

We use the Constitution supernova, the baryon acoustic oscillation, the cosmic microwave background, and the Hubble parameter data to analyze the evolution property of dark energy. We obtain different results when we fit different baryon…

宇宙学与河外天体物理 · 物理学 2014-11-20 Yungui Gong , Rong-Gen Cai , Yun Chen , Zong-Hong Zhu

We present logistic dark energy model (LDEM), where the dark energy density follows a logistic function for the scale factor. The equation of state parameter of dark energy ($w_D$) transitioned from $-1$ in the distant past to its current…

宇宙学与河外天体物理 · 物理学 2024-06-27 Sarath Nelleri , Gopi Krishna , Navaneeth Poonthottathil
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