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Related papers: Exploring Universe acceleration through observatio…

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In this paper, we propose a modified scale factor (MSF) that allows us to explore the accelerating expansion of the universe without invoking the traditional dark-energy model, as described in the Lambda cold dark matter ($\Lambda$CDM)…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-10 Goratamang Gaedie , Shambel Sahlu , Amare Abebe

In this paper, the dynamical behavior of the accelerated expansion of the universe is discussed within the framework of $f(T)$ gravity, considering power law functional form of $ f(T)=\alpha (-T)^{n}$. Two distinct redshift-dependent…

General Relativity and Quantum Cosmology · Physics 2025-08-29 Shivank Pal , Romanshu Garg , Gyan Prakash Singh , Gauree Shanker

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…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Muhammad Omer Farooq

We propose a Friedmann-Lemaitre-Robertson-Walker cosmological model with a scalar field that represents dark energy. A new parametrization of the deceleration parameter is introduced of the form $q = 1 + \eta (1 + \mu a^{\eta})$ where…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-07 Aroonkumar Beesham

We measure the current expansion rate of the Universe, Hubble's constant $H_0$, by calibrating the absolute magnitudes of supernovae to distances measured by Baryon Acoustic Oscillations. This `inverse distance ladder' technique provides an…

We use Pantheon Type Ia supernova (SN Ia) apparent magnitude, DES-3yr binned SN Ia apparent magnitude, Hubble parameter, and baryon acoustic oscillation measurements to constrain six spatially flat and non-flat cosmological models. These…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Shulei Cao , Joseph Ryan , Bharat Ratra

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…

General Relativity and Quantum Cosmology · Physics 2025-06-10 Amit Samaddar , S. Surendra Singh

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-26 M. Koussour , N. S. Kavya , V. Venkatesha , N. Myrzakulov

This study delves into the cosmological implications of the $f(Q,C)$ modified gravity framework within the context of the FLRW spacetime which offers a dynamic alternative to the standard $\Lambda$CDM cosmology. Here, we define the transit…

General Relativity and Quantum Cosmology · Physics 2024-12-03 N. Myrzakulov , Anirudh Pradhan , A. Dixit , S. H. Shekh

We consider nonlinear redshift-dependent equation of state parameters as dark energy models in a spatially flat Friedmann-Lema\^itre-Robertson-Walker universe. To depict the expansion history of the universe in such cosmological scenarios,…

General Relativity and Quantum Cosmology · Physics 2018-02-06 Weiqiang Yang , Supriya Pan , Andronikos Paliathanasis

We consider three `four-parameters' dark energy equations of state allowing fast transition from the matter dominated decelerating phase to the current accelerating phase. The fast-varying nature of the dark energy models is quantified by…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-17 Rafael J. F. Marcondes , Supriya Pan

We quantify the evidence for cosmic acceleration using simulations of $H(z)$ measurements from SKA- and Euclid-like surveys. We perform a non-parametric reconstruction of the Hubble parameters and its derivative to obtain the deceleration…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-06 Carlos A. P. Bengaly

The Hubble constant $H_0$ tension has emerged as the most serious crisis in modern cosmology, potentially indicating that the $\Lambda$CDM model may not describe our universe accurately. In this paper, we establish a new,…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-26 Yang Liu , Bao Wang , Hongwei Yu , Puxun Wu

A parametric reconstruction of the jerk parameter, the third order derivative of the scale factor expressed in a dimensionless way, has been discussed. Observational constraints on the model parameters have been obtained by Maximum…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Ankan Mukherjee , Narayan Banerjee

The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of "dark energy" with exotic physical properties, or that Einstein's theory of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 David H. Weinberg , Michael J. Mortonson , Daniel J. Eisenstein , Christopher Hirata , Adam G. Riess , Eduardo Rozo

The present work is based on a parametric reconstruction of the deceleration parameter $q(z)$ in a model for the spatially flat FRW universe filled with dark energy and non-relativistic matter. In cosmology, the parametric reconstruction…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Abdulla Al Mamon , Sudipta Das

We study the accelerated expansion of the universe by using the kinematic approach. In this context, we parameterize the deceleration parameter, q(z), in a model independent way. Assuming three simple parameterizations we reconstruct q(z).…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Remya Nair , Sanjay Jhingan , Deepak Jain

This work is the reconstruction of the interaction rate of holographic dark energy whose infrared cut-off scale is set by the Hubble length. We have reconstructed the interaction rate between dark matter and the holographic dark energy for…

General Relativity and Quantum Cosmology · Physics 2017-10-04 Abdulla Al Mamon

In this paper, we have proposed a generalized parametrization for the deceleration parameter $q$ in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Abdulla Al Mamon

Since the late 1990's observations of type Ia Supernova, our universe is predicted to experience a late time cosmic acceleration. Theoretical support to this observation were intended to be built via proposition of a hypothetical fluid…

General Relativity and Quantum Cosmology · Physics 2020-08-10 Promila Biswas , Parthajit Roy , Ritabrata Biswas