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Related papers: An Accelerating Flat FLRW Model with Observation C…

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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…

General Relativity and Quantum Cosmology · Physics 2023-06-26 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

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

In this manuscript, we investigate the constraints on dynamical vacuum models within the framework of $\Lambda(t)$CDM cosmology by assuming a parameterization of the vacuum energy density as $\rho_{\Lambda}(t)=\rho_{\Lambda 0} \left[1 +…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-14 Yerlan Myrzakulov , M. Koussour , M. Bulanbay , S. Muminov , J. Rayimbaev

Nojiri \& Odintsov \cite{noj1} and Hu \& Sawicki \cite{hu} have studied non-linear functions in modified gravity that explain the cosmic acceleration without cosmological constant, fulfil the conditions of local gravity \& stability and…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Gauranga C Samanta , Nisha Godani

We investigate the possibility of testing cosmological models with interaction between matter and energy sector. We assume the standard FRW model while the so called energy conservation condition is interpreted locally in terms of energy…

Astrophysics · Physics 2008-11-26 Marek Szydlowski , Tomasz Stachowiak , Radoslaw Wojtak

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is performed adopting the non-parametric Gaussian Processes (GP). The constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-18 Purba Mukherjee , Narayan Banerjee

We proposed a model-independent method to constrain the cosmological parameters using the Distance Sum Rule of the FLRW metric by combining the time delay distances and the comoving distances through a multi-messenger approach. The time…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Yufeng Li , Xilong Fan , Lijun Gou

The inflationary epoch and the late time acceleration of the expansion rate of universe can be explained by assuming a gravitationally coupled scalar field. In this article, we propose a new method of finding exact solutions in the…

General Relativity and Quantum Cosmology · Physics 2022-09-19 Albin Joseph , Rajib Saha

In braneworld models a variable vacuum energy may appear if the size of the extra dimension changes during the evolution of the universe. In this scenario the acceleration of the universe is related not only to the variation of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Ponce de Leon

In a thermodynamical model of cosmological FLRW event horizons for the dark energy (DE), we consider a logarithmic corrective term in the entropy to which corresponds a new term in the DE density. This model of $\Lambda (t)$ in an…

Astrophysics · Physics 2016-08-15 Cécile Barbachoux , Jérome Gariel , Gérard Le Denmat

In this paper We have investigated a homogeneous and isotropic FRW cosmological model with perfect fluid in the framework of $f(R,Lm)$ gravity. We have explored for the non linear case of $f(R,L_m)$ model, namely $f(R,L_m) = R/2 + L_m$ and…

General Relativity and Quantum Cosmology · Physics 2023-06-19 Bhupendra Kumar Shukla , Rishi KumarTiwari , Deger Sufuoglu , Aroonkumar Beesham

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

The dispersion measure-redshift relation of fast radio bursts (FRBs) provides a valuable cosmological probe for constraining the Hubble constant, offering an independent measurement that could help resolve the ongoing Hubble tension. In…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-28 Chenyuan Xu , Yi Feng , Jiaying Xu

A major issue in contemporary cosmology is the persistent discrepancy, known as the Hubble tension, between the Hubble constant ($H_0$) estimates from local measurements and those inferred from early-Universe observations under the standard…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-29 Surajit Kalita , Akhil Uniyal , Tomasz Bulik , Yosuke Mizuno

One of the most significant discoveries in modern cosmology is that the universe is currently in a phase of accelerated expansion after a switch from a decelerated expansion. The redshift corresponding to this epoch is referred to as the…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-18 Darshan Kumar , Deepak Jain , Shobhit Mahajan , Amitabha Mukherjee , Akshay Rana

The Hubble constant ($H_0$) measures the current expansion rate of the Universe, and plays a fundamental role in cosmology. Tremendous effort has been dedicated over the past decades to measure $H_0$. Notably, Planck cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-02 Kenta Hotokezaka , Ehud Nakar , Ore Gottlieb , Samaya Nissanke , Kento Masuda , Gregg Hallinan , Kunal P. Mooley , Adam. T. Deller

Fast radio bursts (FRBs) are among the most mysterious astronomical transients. Due to their short durations and cosmological distances, their dispersion measure (DM) - redshift ($z$) relation is useful for constraining cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-07 Jiaming Zhuge , Marios Kalomenopoulos , Bing Zhang

We study the dynamics of the FLRW flat cosmological models in which the vacuum energy density varies with time, $\Lambda(t)$. In particular, we investigate the dynamical properties of a generalized vacuum model and we find that under…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Spyros Basilakos

Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…

General Physics · Physics 2026-03-10 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

In this paper, cosmic distance duality relation is probed without considering any background cosmological model. The only \textit{a priori} assumption is that the Universe is described by the Friedmann-Lema$\hat{i}$tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2025-01-28 Savita Gahlaut
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