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Using the mathematical definitions of deceleration and jerk parameters we obtain a general differential equation for squared Hubble parameter. For a constant jerk, this differential equation leads to an exact function for Hubble parameter.…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-21 Hassan Amirhashchi , Soroush Amirhashchi

The growing field of large-scale time domain astronomy requires methods for probabilistic data analysis that are computationally tractable, even with large datasets. Gaussian Processes are a popular class of models used for this purpose…

Instrumentation and Methods for Astrophysics · Physics 2017-11-15 Daniel Foreman-Mackey , Eric Agol , Sivaram Ambikasaran , Ruth Angus

We use cosmography to present constraints on the kinematics of the Universe, without postulating any underlying theoretical model. To this end, we use a Monte Carlo Markov Chain analysis to perform comparisons to the supernova Ia Union 2…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo

We perform a cosmographic analysis using several cosmological observables such as the luminosity distance moduli, the volume distance, the angular diameter distance and the Hubble parameter. These quantities are determined using different…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jun-Qing Xia , Vincenzo Vitagliano , Stefano Liberati , Matteo Viel

The Hubble diagram is one of the cornerstones of observational cosmology. It is usually analysed assuming that, on average, the underlying relation between magnitude and redshift matches the prediction of a…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Pierre Fleury , Chris Clarkson , Roy Maartens

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

Using a model-independent analysis method which bases on the Lagrange mean value theorem for obtaining the derivative of the Hubble function, we analyze $H(z)$ parameter data with some restrictive conditions. We find that: (a) the Universe…

General Relativity and Quantum Cosmology · Physics 2025-12-11 Rong-Jia Yang

We present a novel formulation for the Hubble parameter derived from Newtonian cosmology, incorporating non-commutative fluid dynamics through a deformed Poisson bracket structure. This approach introduces a new cosmological parameter,…

General Relativity and Quantum Cosmology · Physics 2026-02-13 Raj Kumar Das , Arpan Krishna Mitra

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

Simulation based inference has seen increasing interest in the past few years as a promising approach to model the non linear scales of galaxy clustering. The common approach using Gaussian process is to train an emulator over the…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-20 Tyann Dumerchat , Julian Bautista

Reconstructing the evolution history of the dark energy equation of state parameter $w(z)$ directly from observational data is highly valuable in cosmology, since it contains substantial clues in understanding the nature of the accelerated…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Zhi-E Liu , Hao-Ran Yu , Tong-Jie Zhang , Yan-Ke Tang

Constraints on the main cosmological parameters using CMB or large scale structure data are usually based on power-law assumption of the primordial power spectrum (PPS). However, in the absence of a preferred model for the early universe,…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Dhiraj Kumar Hazra , Arman Shafieloo , Tarun Souradeep

The measurement of cosmological parameters is investigated in a representation of the least-action method that uses a redshift-space dataset to simultaneously constrain the real-space fields $\delta$,$\b v$. This method is robust in…

Astrophysics · Physics 2009-10-31 Mikel Susperregi

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 accelerated cosmic expansion could be due to dark energy within general relativity (GR), or modified gravity. It is of interest to differentiate between them, by using both the expansion history and the growth history. In the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-07 Zhao-Yu Yin , Hao Wei

In modern cosmology, the rapid growth of high-precision observational data, along with significant theoretical advances, has intensified the challenge of identifying a robust, model-independent framework to probe the expansion history of…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-30 Yuki Hashimoto , Kazuharu Bamba , Sanjay Mandal

For a large class of dark energy (DE) models, for which the effective gravitational constant is a constant and there is no direct exchange of energy between DE and dark matter (DM), knowledge of the expansion history suffices to reconstruct…

Astrophysics · Physics 2010-05-27 Ujjaini Alam , Varun Sahni , Alexei A. Starobinsky

Dark energy is believed to be responsible for the acceleration of the universe. In this paper, we reconstruct the dark energy scalar field potential $V(\phi)$ using the Hubble parameter $H(z)$ through Gaussian Process analysis. Our goal is…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Jing Niu , Kang Jiao , Peng He , Tong-Jie Zhang

These days we live in a world with a permanent electromagnetic field. This raises many questions about our health and the deployment of new equipment. The problem is that these fields remain difficult to visualize easily, which only some…

Signal Processing · Electrical Eng. & Systems 2022-03-04 Angesom Ataklity Tesfay , Laurent Clavier

In view of late-time cosmic acceleration, a dark energy cosmological model is revisited wherein Einstein's cosmological constant is considered as a candidate of dark energy. Exact solution of Einstein field equations (EFEs) is derived in a…

General Relativity and Quantum Cosmology · Physics 2019-11-22 S. K. J. Pacif , Md Salahuddin Khan , L. K. Paikroy , Shalini Singh
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