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Related papers: Exploring Universe acceleration through observatio…

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In this study, we present an approach $ f(R, G) $ gravity incorporating power law in $ G $. To study the cosmic evolution of the universe given by the reconstruction of the Hubble parameter given by $ E(z) = \bigg(…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Rita Rani , Shaily , G. K. Goswami , J. K. Singh

We present a cosmographic study designed to test the simplest type of accelerating cosmology: a flat universe with matter and a cosmological constant ($\Lambda$). Hubble series expansions are fit to the SCP Union2.1 supernova data set to…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-17 Brett Bochner , Damon Pappas , Menglu Dong

Inspired by the string axiverse idea, it has been suggested that the recent transition from decelerated to accelerated cosmic expansion is driven by an axion-like quintessence field with a sub-Planckian decay constant. The scenario requires…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-05 Razieh Emami , Daniel Grin , Josef Pradler , Alvise Raccanelli , Marc Kamionkowski

The presented paper is a comprehensive analysis of two dark energy (DE) cosmological models wherein exact solutions of the Einstein field equations (EFEs) are obtained in a model-independent way (or by cosmological parametrization). A…

General Physics · Physics 2022-07-20 S. K. J. Pacif

Compared with the plentiful researches of the Hubble parameter and deceleration factor, the third time derivative of the scale factor $a(t)$ in the FRW cosmology, namely, the jerk parameter $j$ still lacks attention. In order to study the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Zhong-Xu Zhai , Ming-Jian Zhang , Zhi-Song Zhang , Xian-Ming Liu , Tong-Jie Zhang

We measure the expansion rate of the recent Universe and the calibration scale of the baryon acoustic oscillation (BAO) from low-redshift data. BAO relies on the calibration scale, i.e., the sound horizon at the end of drag epoch $r_d$,…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-17 Xue Zhang , Qing-Guo Huang

In the early seventies, Alan Sandage defined cosmology as the search for two numbers: Hubble parameter ${{H}_{0}}$ and deceleration parameter ${{q}_{0}}$. The first of the two basic cosmological parameters (the Hubble parameter) describes…

General Relativity and Quantum Cosmology · Physics 2015-02-04 Yu. L. Bolotin , V. A. Cherkaskiy , O. A. Lemets , D. A. Yerokhin , L. G. Zazunov

Over the last 20 years, supernovae have become a key tool to constrain the expansion history of the Universe through the construction of Hubble diagrams, using luminosity distances to supernovae belonging to the "Ia" subtype. This technique…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-13 Pierre Astier

The deceleration parameter q as the diagnostic of the cosmological accelerating expansion is investigated. By expanding the luminosity distance to the fourth order of redshift and the so-called y-redshift in two redshift bins and fitting…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ronggen Cai , Zhongliang Tuo

In a recent paper \cite{Artymowski:2020zwy} we suggested the possibility that the present acceleration of the Universe is due to thermodynamical behavior of unparticles. The model is free of scalar fields, modified gravity, a Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 Michał Artymowski , Ido Ben-Dayan , Utkarsh Kumar

We study non-viscous and viscous holographic dark energy models for a homogeneous and isotropic flat Friedmann-Robertson-Walker Universe in $f(R,T)$ gravity. We find that the Hubble horizon as an IR cut-off is suitable for both the models…

General Relativity and Quantum Cosmology · Physics 2015-10-15 C. P. Singh , Pankaj Kumar

One of the most compelling tasks of modern cosmology is to constrain the expansion history of the Universe, since this measurement can give insights on the nature of dark energy and help to estimate cosmological parameters. In this letter…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Michele Moresco

We investigate a late-time cosmological model for a homogeneous and isotropic space-time in the Rastall theory. We explore the observational constraints on the Hubble parameter by using the latest cosmological datasets such as cosmic…

General Relativity and Quantum Cosmology · Physics 2026-01-01 Vinod Kumar Bhardwaj , Saibal Ray , Kazuharu Bamba , Akram Ali

We perform a model independent reconstruction of the cosmic expansion rate based on type Ia supernova data. Using the Union 2.1 data set, we show that the Hubble parameter behaviour allowed by the data without making any hypothesis about…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Benitez-Herrera , E. E. O. Ishida , M. Maturi , W. Hillebrandt , M. Bartelmann , F. Röpke , .

A model-independent reconstruction of the cosmic expansion rate is essential to a robust analysis of cosmological observations. Our goal is to demonstrate that current data are able to provide reasonable constraints on the behavior of the…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-17 Emille E. O. Ishida , Rafael S. de Souza

We work out an effective theory of accelerated expansion to describe general phenomena of inflation and acceleration (dark energy) in the Universe. Our aim is to determine from theoretical grounds, in a physically-motivated and model…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Raul Jimenez , P. Talavera , Licia Verde

A recently proposed Asymptotically Safe cosmology provides an elegant mechanism towards understanding the nature of dark energy and its associated cosmic coincidence problem. The underlying idea is that the accelerated expansion of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Fotios K. Anagnostopoulos , Spyros Basilakos , Georgios Kofinas , Vasilios Zarikas

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to perform our analyses, we consider a flat universe and {assume}…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-31 J. F. Jesus , R. F. L. Holanda , S. H. Pereira

In this paper, we explore power law solution of FLRW universe model that is associated with a variable cosmological term $\Lambda(t)$ as a linear function of $\frac{\ddot{a}}{a}, (\frac{\dot{a}}{a})^2$ and $\rho$. The model parameters were…

General Physics · Physics 2025-04-28 G. K. Goswami , Anirudh Pradhan

In this paper, linear first order expansion of deceleration parameter $q(z)=q_0+q_1(1-a)$ ($M_1$), constant jerk $j=j_0$ ($M_2$) and third order expansion of luminosity distance ($M_3$) are confronted with cosmic observations: SCP 307 SN…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Lixin Xu , Wenbo Li , Jianbo Lu