English
Related papers

Related papers: High-redshift cosmography: auxiliary variables ver…

200 papers

The limits of standard cosmography are here revised addressing the problem of error propagation during statistical analyses. To do so, we propose the use of Chebyshev polynomials to parameterize cosmic distances. In particular, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

Given observations of the standard candles and the cosmic chronometers, we apply Pad\'{e} parameterization to the comoving distance and the Hubble paramter to find how stringent the constraint is set to the curvature parameter by the data.…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Shi-Yu Li , Yun-Long Li , Tong-Jie Zhang , Tingting Zhang

In the present paper, we investigate the cosmographic problem using the bias-variance trade-off. We find that both the z-redshift and the $y=z/(1+z)$-redshift can present a small bias estimation. It means that the cosmography can describe…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-13 Ming-Jian Zhang , Hong Li , Jun-Qing Xia

With the use of simulated supernova catalogs, we show that the statefinder parameters turn out to be poorly and biased estimated by standard cosmography. To this end, we compute their standard deviations and several bias statistics on…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-09 Alejandro Aviles , Jaime Klapp , Orlando Luongo

Pad$\acute{e}$ cosmography has been widely used to probe the cosmic evolution and to investigate the nature of dark energy. In this paper, we find that the Pad$\acute{e}$ approximant can describe the cosmic evolution better than the…

General Relativity and Quantum Cosmology · Physics 2021-12-24 Yang Liu , Zhengxiang Li , Hongwei Yu , Puxun Wu

Context. Explaining the accelerated expansion of the Universe is one of the fundamental challenges in physics today. Cosmography provides information about the evolution of the universe derived from measured distances, assuming only that…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 Marek Demianski , Ester Piedipalumbo , Disha Sawant , Lorenzo Amati

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 cosmography known as the Pad\'{e} polynomials has been widely used in the reconstruction of luminosity distance, and the orders of Pad\'{e} polynomials influence the reconstructed result derived from Pad\'{e} approximation. In this…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-24 Bo Yu , Wenhu Liu , XiaoFeng Yang , Tong-Jie zhang , Yanke Tang

Cosmological observations usually map our present-day past light cone. However, it is also possible to compare different past light cones. This is the concept behind the redshift drift, a model-independent probe of fundamental cosmology. In…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 C. S. Alves , A. C. O. Leite , C. J. A. P. Martins , J. G. B. Matos , T. A. Silva

Cosmology constraints serve as a crucial criterion in discriminating cosmological models. The traditional combined method to constrain the cosmological parameters designates the corresponding theoretical value and observational data as…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-17 Wei Hong , Kang Jiao , Yu-Chen Wang , Tingting Zhang , Tong-Jie Zhang

We present a comprehensive study of the observational constraints on spatially flat cosmological models containing a mixture of matter and quintessence --- a time varying, spatially inhomogeneous component of the energy density of the…

Astrophysics · Physics 2009-09-15 Limin Wang , R. R. Caldwell , J. P. Ostriker , Paul J. Steinhardt

The Hubble relation between distance and redshift is a purely cosmographic relation that depends only on the symmetries of a FLRW spacetime, but does not intrinsically make any dynamical assumptions. This suggests that it should be possible…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Celine Cattoen , Matt Visser

The cosmographic approach is gaining considerable interest as a model-independent technique able to describe the late expansion of the universe. Indeed, given only the observational assumption of the cosmological principle, it allows to…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Micol Benetti , Salvatore Capozziello

Stage IV cosmological surveys will map the universe with unprecedented precision, reducing statistical uncertainties to levels where unmodelled systematics can significantly bias inference. In particular, photometric redshift (photo-z)…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-11 Carolyn McDonald Mill , C. Danielle Leonard , Markus Michael Rau , Cora Uhlemann , Shahab Joudaki

The search for a physical model which explains the observed recent acceleration of the universe is a compelling task of modern fundamental cosmology. Recently Fernandes \textit{et al.} presented low redshift observational constraints on a…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-01 C. J. A. P. Martins , J. S. J. S. Oliveira , D. A. R. Pinheiro

The transition redshift (deceleration/acceleration) is discussed by expanding the deceleration parameter to first order around its present value. A detailed study is carried out by considering two different parameterizations: $q=q_0 + q_1z$…

Astrophysics · Physics 2011-02-11 J. V. Cunha , J. A. S. Lima

We estimate how clustering in large-scale redshift surveys can constrain various cosmological parameters. Depth and sky coverage of modern redshift surveys are greater than ever, opening new possibilities for statistical analysis. We have…

Astrophysics · Physics 2009-11-07 Takahiko Matsubara , Alexander S. Szalay

In this paper, we present a cosmological model-independent test for the cosmic opacity at high redshifts ($z\sim5$). We achieve this with the opacity-dependent luminosity distances derived from nonlinear relation between X-ray and UV…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-19 Tonghua Liu , Shuo Cao , Marek Biesiada , Yuting Liu , Shuaibo Geng , Yujie Lian

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to perform our analyses, we consider a flat universe and {assume}…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-31 J. F. Jesus , R. F. L. Holanda , S. H. Pereira

By the use of homotopy perturbation method-Pad\'e (HPM-Pad\'e) technique, a new analytical approximation of luminosity distance in the flat universe is proposed, which has the advantage of significant improvement for accuracy in…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-20 Bo Yu , Jian-Chen Zhang , Tong-Jie Zhang , Tingting Zhang