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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

Cosmography is a useful tool to constrain cosmological models, in particular dark energy models. In the case of modified theories of gravity, where the equations of motion are generally quite complicated, cosmography can contribute to…

General Relativity and Quantum Cosmology · Physics 2010-12-23 Mariam Bouhmadi-Lopez , Salvatore Capozziello , Vincenzo F. Cardone

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

We propose and implement a novel, robust, and non-parametric test of statistical isotropy of the expansion of the universe, and apply it to around one thousand type Ia supernovae from the Pantheon sample. We calculate the angular clustering…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-24 John Soltis , Arya Farahi , Dragan Huterer , C. Michael Liberato

Cosmic Microwave Background (CMB) anisotropy encodes a lot of information about our Universe. In this paper we take the ground-based CMB observations (GCMB), including the South Pole Telescope (SPT), SPTpol and the Atacama Cosmology…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Ke Wang , Qing-Guo Huang

We suggest that the solution to the cosmological vacuum energy puzzle does not require any new field beyond the standard model, but rather can be explained as a result of the interaction of the infrared sector of the effective theory of…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 Federico R. Urban , Ariel R. Zhitnitsky

We present a new, cosmologically model-independent, statistical analysis of the Pantheon+ type Ia supernovae spectroscopic dataset, improving a standard methodology adopted by Lane et al. We use the Tripp equation for supernova…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 Antonia Seifert , Zachary G. Lane , Marco Galoppo , Ryan Ridden-Harper , David L. Wiltshire

Recently, an anisotropic cosmological model was proposed. An arbitrary 1-form, which picks out a privileged axis in the universe, was added to the Friedmann-Robertson-Walker line element. The distance-redshift relation was modified such…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-14 Zhe Chang , Xin Li , Hai-Nan Lin , Sai Wang

In this work we present the first results from a new ray-tracing tool to calculate cosmological distances in the context of fully nonlinear general relativity. We use this tool to study the ability of the general cosmographic representation…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Hayley J. Macpherson

The Hubble constant $H_0$ tension has emerged as the most serious crisis in modern cosmology, potentially indicating that the $\Lambda$CDM model may not describe our universe accurately. In this paper, we establish a new,…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-26 Yang Liu , Bao Wang , Hongwei Yu , Puxun Wu

We discuss recently published results of two-dimensional measurements of the cosmic ray anisotropy in the energy range 1-100 TeV. It is demonstrated that, in spite of pretence of the authors to measure the anisotropy in more detail than it…

Astrophysics · Physics 2008-04-29 Yu. M. Andreyev , V. A. Kozyarivsky , A. S. Lidvansky

Cosmography represents an important branch of cosmology which aims to describe the universe without the need of postulating \emph{a priori} any particular cosmological model. All quantities of interest are expanded as a Taylor series around…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Peter K. S. Dunsby , Orlando Luongo

Analyses of recent cosmic microwave background (CMB) observations have provided increasing indications for the existence of large scale anisotropy in the universe. Given the far reaching consequences of such an anisotropy for our…

Astrophysics · Physics 2009-09-29 A. Bernui , B. Mota , M. J. Reboucas , R. Tavakol

We present a novel approach to disentangle two key contributions to the largest-scale anisotropy of the galaxy distribution: (i) the intrinsic dipole due to clustering and anisotropic geometry, and (ii) the kinematic dipole due to our…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-09 Tobias Nadolny , Ruth Durrer , Martin Kunz , Hamsa Padmanabhan

We investigate possible astronomical manifestations of space-time anisotropy. The homogeneous vacuum Kasner solution was chosen as a reference anisotropic cosmological model because there are no effects caused by inhomogeneity in this…

General Relativity and Quantum Cosmology · Physics 2023-05-30 S L Parnovsky

We propose a method based on the redshift dependence of the Alcock-Paczynski (AP) test to measure the expansion history of the Universe. It uses the isotropy of the galaxy density gradient field to constrain cosmological parameters. If the…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-30 Xiao-Dong Li , Changbom Park , Jaime E. Forero-Romero , Juhan Kim

The Cosmological Principle states that the Universe is statistically isotropic and homogeneous on large scales. In particular, this implies statistical isotropy in the galaxy distribution, after removal of a dipole anisotropy due to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-16 Carlos A. P. Bengaly , Roy Maartens , Nandrianina Randriamiarinarivo , Albert Baloyi

We present the analysis of the full shape of anisotropic clustering measurement from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) quasar sample together with the combined galaxy sample from the Baryon Oscillation…

Assuming that the cosmological principle holds, Maartens, Ellis and Stoeger (MES) recently constructed a detailed scheme linking anisotropies in the cosmic background radiation (CMB) with anisotropies and inhomogeneities in the large scale…

Astrophysics · Physics 2008-12-01 William Stoeger , Marcelo Araujo , Tim Gebbie

The cosmological principle states that the Universe is statistically homogeneous and isotropic at large distance scales. There currently exist many observations which indicate a departure from this principle. It has been shown that many of…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-31 Shamik Ghosh , Pankaj Jain , Rahul Kothari , Mohit Panwar , Gurmeet Singh , Prabhakar Tiwari
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