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Related papers: Constraints on a generalized deceleration paramete…

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We propose, and constrain with the latest observational data, three model-independent parametrizations of the cosmic deceleration parameter $q(z)$. They are well behaved and stay finite at all redshifts. We construct them by fixing the…

General Relativity and Quantum Cosmology · Physics 2012-10-16 Sergio del Campo , Ivan Duran , Ramon Herrera , Diego Pavon

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

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})…

General Relativity and Quantum Cosmology · Physics 2025-01-10 Y. Kalpana Devi , S. A. Narawade , B. Mishra

For different gravitational models we consider limitations on their parameters coming from recent observational data for type Ia supernovae, baryon acoustic oscillations, and from 34 data points for the Hubble parameter $H(z)$ depending on…

General Relativity and Quantum Cosmology · Physics 2014-11-06 G. S. Sharov , E. G. Vorontsova

We compile a list of 28 independent measurements of the Hubble parameter between redshifts 0.07 < z < 2.3 and use this to place constraints on model parameters of constant and time-evolving dark energy cosmologies. These H(z) measurements…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Omer Farooq , Bharat Ratra

The current paper reports an investigation of the cosmological implications of symmetric teleparallel gravity within a modified $f(Q)$ theory. We construct a specific exponential $f(Q)$ model as $f(Q) = Q + \eta_1 Q_0\left(1 - e^{-\eta_2…

General Relativity and Quantum Cosmology · Physics 2025-11-11 Sanjeeda Sultanaa , Surajit Chattopadhyay

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

In a model of the late-time cosmic acceleration within the framework of generalized Proca theories, there exists a de Sitter attractor preceded by the dark energy equation of state $w_{\rm DE}=-1-s$, where $s$ is a positive constant. We run…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-05 Antonio De Felice , Lavinia Heisenberg , Shinji Tsujikawa

We explore the observational adequacy of a class of Unified Dark Energy/Matter (UDE/M) models with a fast transition. Our constraints are set using a combination of geometric probes, some low redshift ones, and some high redshift ones (CMB…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Ruth Lazkoz , Iker Leanizbarrutia , Vincenzo Salzano

We consider several well-known f(R) cosmological models and constrain their parameters, namely the deviation parameter b and the cosmological parameters \Omega_m and h. We first obtain analytical approximations for the Hubble rate H(z) and…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Joseph Sultana , Manoj K. Yennapureddy , Fulvio Melia , Demosthenes Kazanas

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,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-09 M. Koussour , N. Myrzakulov , S. Myrzakulova , D. Sofuoğlu

We propose a new parametrization of the deceleration parameter to study its time-variation behavior. The advantage of parameterizing the deceleration parameter is that we do not need to assume any underlying theory of gravity. By fitting…

Astrophysics · Physics 2008-11-26 Yungui Gong , Anzhong Wang

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…

General Relativity and Quantum Cosmology · Physics 2023-07-04 A. Mussatayeva , N. Myrzakulov , M. Koussour

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…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-16 Yan Liu , Rui-Yun Guo , Jing-Fei Zhang , Xin Zhang

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

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

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-06 L. Sudharani , Kazuharu Bamba , N. S. Kavya , V. Venkatesha

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

Astrophysics · Physics 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

This study explores a distinctive logarithmic parameterization of the deceleration parameter within the $f(Q, C)$ gravity framework, incorporating a nonlinear functional form $f(Q, C) = \gamma_1 Q^n + \gamma_2 C$, where $Q$ and $C$ denote…

General Relativity and Quantum Cosmology · Physics 2025-06-03 S. R. Bhoyar , Yash B. Ingole