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Related papers: Constraints on Cosmographic Functions of Cosmic Ch…

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Cosmographic approach, a Taylor expansion of the Hubble function, has been used as a model-independent method to investigate the evolution of the universe in the presence of cosmological data. Apart from possible technical problems like the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-04 Ahmad Mehrabi , Mehdi Rezaei

The standard cosmographic approach consists in performing a series expansion of a cosmological observable around $z=0$ and then using the data to constrain the cosmographic (or kinematic) parameters at present time. Such a procedure works…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 C. Rodrigues Filho , Edésio M. Barboza

By using recent $H(z)$ and SNe Ia data, we reconstruct the evolution of kinematic parameters $H(z)$, $q(z)$, jerk and snap, using a model-independent, non-parametric method, namely, the Gaussian Processes. Throughout the present analysis,…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-29 J. F. Jesus , D. Benndorf , S. H. Pereira , A. A. Escobal

The use of Gaussian Processes with a measurement of the cosmic expansion rate based solely on the observation of cosmic chronometers provides a completely cosmology-independent reconstruction of the Hubble constant H(z) suitable for testing…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-21 Fulvio Melia , Manoj K. Yennapureddy

The current accelerated expansion of the Universe remains ones of the most intriguing topics in modern cosmology, driving the search for innovative statistical techniques. Recent advancements in machine learning have significantly enhanced…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-03 José de Jesús Velázquez , Luis A. Escamilla , Purba Mukherjee , J. Alberto Vázquez

Gaussian processes provide a method for extracting cosmological information from observations without assuming a cosmological model. We carry out cosmography -- mapping the time evolution of the cosmic expansion -- in a model-independent…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-11 Arman Shafieloo , Alex G. Kim , Eric V. Linder

In the current work, we have implemented an extension of the standard Gaussian Process formalism, namely the Multi-Task Gaussian Process with the ability to perform a joint learning of several cosmological data simultaneously. We have…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Balakrishna S. Haridasu , Vladimir V. Luković , Michele Moresco , Nicola Vittorio

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

Using mock data for the Hubble diagrams of type Ia supernovae (SNIa) and quasars (QSOs) generated based on the standard model of cosmology, and using the least-squares method based on the Markov-Chain-Monte-Carlo (MCMC) algorithm, we first…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-04 S. Pourojaghi , N. F. Zabihi , M. Malekjani

We apply two methods, namely the Gaussian processes and the non-parametric smoothing procedure, to reconstruct the Hubble parameter $H(z)$ as a function of redshift from 15 measurements of the expansion rate obtained from age estimates of…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Zhengxiang Li , J. E. Gonzalez , Hongwei Yu , Zong-Hong Zhu , J. S. Alcaniz

Recent cosmological observations have achieved high-precision measurements of the Universe's expansion history, prompting the use of nonparametric methods such as Gaussian processes (GP) regression. We apply GP regression for reconstructing…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-21 Jia-yan Jiang , Kang Jiao , Tong-Jie Zhang

In this paper, we study the cosmological constraints from the measurements of Hubble parameters---$H(z)$ data. Here, we consider two kinds of $H(z)$ data: the direct $H_0$ probe from the Hubble Space Telescope (HST) observations of Cepheid…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-31 Wei Zheng , Hong Li , Jun-Qing Xia , You-Ping Wan , Si-Yu Li , Mingzhe Li

We apply Gaussian processes (GP) in order to impose constraints on teleparallel gravity and its $f(T)$ extensions. We use available $H(z)$ observations from (i) cosmic chronometers data (CC); (ii) Supernova Type Ia (SN) data from the…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Rebecca Briffa , Salvatore Capozziello , Jackson Levi Said , Jurgen Mifsud , Emmanuel N. Saridakis

Measurement of the universe expansion rate through the cosmic chronometers proves to be a novel approach to understanding cosmic history. Although it provides a direct determination of the Hubble parameters at different redshifts, it…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-12 Faeze Jalilvand , Ahmad Mehrabi

The challenging issue of determining the correct $f(R)$ among several possibilities is here revised by means of numerical reconstructions of the modified Friedmann equations around the redshift interval $z\in[0,1]$. Frequently, a severe…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Liberato Pizza

A natural extension of the standard cosmological model are models that include curvature as a free parameter. In this work we study in detail the observational constraints on the non-flat $\Lambda CDM$ model using the two main geometric…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-15 Velasquez-Toribio , A. M , Magnago , A. dos R

We constrain the parameters describing the kinematical state of the universe using a cosmographic approach, which is fundamental in that it requires a very minimal set of assumptions (namely to specify a metric) and does not rely on the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

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 use the redshift Hubble parameter $H(z)$ data derived from relative galaxy ages, distant type Ia supernovae (SNe Ia), the Baryonic Acoustic Oscillation (BAO) peak, and the Cosmic Microwave Background (CMB) shift parameter data, to…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Tian Lan , Yan Gong , Hao-Yi Wan , Tong-Jie Zhang

Cosmic chronometers offer a model-independent way to trace the expansion history of the Universe via the dating of passively evolving objects. This enables testing the validity of cosmological models without concrete assumptions of their…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-05 Carlos A. Álvarez , Marcos M. Cueli , Alessandro Bressan , Lumen Boco , Balakrishna S. Haridasu , Michele Bosi , Luigi Danese , Andrea Lapi
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