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相关论文: Model-independent reconstruction of the cosmologic…

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In the present work we describe a model-independent method of developing a plot of scale factor versus lookback time from the usual Hubble diagram of modulus data against redshift. This is the first plot of this type. We follow the…

宇宙学与河外天体物理 · 物理学 2015-06-22 Harry I. Ringermacher , Lawrence R. Mead

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…

宇宙学与河外天体物理 · 物理学 2015-06-24 Liberato Pizza

We propose a new model-independent reconstruction method for the matter power spectrum based on its time dependence and a combination of observations from different redshifts. The method builds on a perturbative expansion in terms of the…

宇宙学与河外天体物理 · 物理学 2024-11-12 Gen Ye , Jun-Qian Jiang , Alessandra Silvestri

Accurately measuring the Hubble parameter is vital for understanding the expansion history and properties of the universe. In this paper, we propose a new method that supplements the covariance between redshift pairs to improve the…

宇宙学与河外天体物理 · 物理学 2024-01-23 Jian-Chen Zhang , Yu Hu , Kang Jiao , Hong-Feng Wang , Yuan-Bo Xie , Bo Yu , Li-Li Zhao , Tong-Jie Zhang

In this paper, we use genetic algorithms, a specific machine learning technique, to achieve a model-independent reconstruction of $f(T)$ gravity. By using $H(z)$ data derived from cosmic chronometers and radial Baryon Acoustic Oscillation…

宇宙学与河外天体物理 · 物理学 2025-06-09 Redouane El Ouardi , Amine Bouali , Imad El Bojaddaini , Ahmed Errahmani , Taoufik Ouali

We apply Gaussian processes and Hubble function data in $f(T)$ cosmology, to reconstruct for the first time the $f(T)$ form in a model-independent way. In particular, using $H(z)$ datasets coming from cosmic chronometers as well as from the…

宇宙学与河外天体物理 · 物理学 2020-01-09 Yi-Fu Cai , Martiros Khurshudyan , Emmanuel N. Saridakis

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…

宇宙学与河外天体物理 · 物理学 2012-05-17 Emille E. O. Ishida , Rafael S. de Souza

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…

宇宙学与河外天体物理 · 物理学 2023-04-12 Faeze Jalilvand , Ahmad Mehrabi

We study the power of current and future observational Hubble parameter data (OHD) on non-parametric estimations of the dark energy equation of state, $w(z)$. We propose a new method by conjunction of principal component analysis (PCA) and…

宇宙学与河外天体物理 · 物理学 2013-11-28 Hao-Ran Yu , Shuo Yuan , Tong-Jie Zhang

In this work, we reconstruct the H(z) based on observational Hubble data with Artificial Neural Network, then estimate the cosmological parameters and the Hubble constant. The training data we used are covariance matrix and mock H(z), which…

宇宙学与河外天体物理 · 物理学 2025-09-23 Jie-feng Chen , Tong-Jie Zhang , Peng He , Tingting Zhang , Jie Zhang

We propose a model-independent formalism to numerically solve the modified Friedmann equations in the framework of $f(T)$ teleparallel cosmology. Our strategy is to expand the Hubble parameter around the redshift $z=0$ up to a given order…

广义相对论与量子宇宙学 · 物理学 2017-11-01 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

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…

宇宙学与河外天体物理 · 物理学 2018-09-21 Fulvio Melia , Manoj K. Yennapureddy

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…

宇宙学与河外天体物理 · 物理学 2016-03-02 Zhengxiang Li , J. E. Gonzalez , Hongwei Yu , Zong-Hong Zhu , J. S. Alcaniz

The cosmic curvature ($\Omega_k$) is a fundamental parameter for cosmology. In this paper, we propose an improved model-independent method to constrain the cosmic curvature, which is geometrically related to the Hubble parameter $H(z)$ and…

宇宙学与河外天体物理 · 物理学 2020-10-07 Yuting Liu , Shuo Cao , Tonghua Liu , Xiaolei Li , Shuaibo Geng , Yujie Lian , Wuzheng Guo

We perform a model-independent investigation of the thermodynamic evolution of the Universe by reconstructing the expansion history from observational data using Gaussian Process regression. We consider three independent combinations of…

宇宙学与河外天体物理 · 物理学 2026-04-22 Afaq Maqsood , Tanima Duary

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…

宇宙学与河外天体物理 · 物理学 2016-08-31 Zhi-E Liu , Hao-Ran Yu , Tong-Jie Zhang , Yan-Ke Tang

In light of the statistical performance of cosmological observations, in this work we present an improvement on the Gaussian reconstruction of the Hubble parameter data $H(z)$ from Cosmic Chronometers, Supernovae Type Ia and Clustering…

宇宙学与河外天体物理 · 物理学 2021-07-28 Mauricio Reyes , Celia Escamilla-Rivera

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…

宇宙学与河外天体物理 · 物理学 2015-06-15 Zhong-Xu Zhai , Ming-Jian Zhang , Zhi-Song Zhang , Xian-Ming Liu , Tong-Jie Zhang

We examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance $\Lambda$CDM cosmology. Strong deviations are allowed by the data at…

宇宙学与河外天体物理 · 物理学 2019-03-19 Benjamin L'Huillier , Arman Shafieloo , Eric V. Linder , Alex G. Kim

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This…

宇宙学与河外天体物理 · 物理学 2019-08-08 Radosław Wojtak , Francisco Prada
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