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Related papers: Anisotropy in Pantheon+ supernovae

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We perform a model independent reconstruction of the cosmic expansion rate based on type Ia supernova data. Using the Union 2.1 data set, we show that the Hubble parameter behaviour allowed by the data without making any hypothesis about…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Benitez-Herrera , E. E. O. Ishida , M. Maturi , W. Hillebrandt , M. Bartelmann , F. Röpke , .

The difference from 4 to 6 $\sigma$ in the Hubble constant ($H_0$) between the values observed with the local (Cepheids and Supernovae Ia, SNe Ia) and the high-z probes (CMB obtained by the Planck data) still challenges the astrophysics and…

We explore the Hubble tension within an anisotropic cosmological framework by revisiting the Bianchi type-I model introduced in Le Delliou et al. 2020. Motivated by ongoing debates surrounding back-reaction effects and observed anomalies in…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-23 Maksym Deliyergiyev , Morgan Le Delliou , Antonino Del Popolo

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

The all-sky maps of the observed variation of the Hubble constant can be reproduced from a theoretical point of view by introducing an intergalactic plasma with a variable number density of electrons. The observed averaged value and…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-30 L. Zaninetti

We probe the anisotropy of the large-scale structure (LSS) with the WISE-2MASS catalogue. This analysis is performed by a directional comparison of the galaxy number counts through the entire celestial sphere once systematic effects, such…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-23 C. A. P. Bengaly , A. Bernui , J. S. Alcaniz , H. S. Xavier , C. P. Novaes

By relaxing the constraint of adiabatic universe used in most cosmological models, we have shown that the new approach provides a better fit to the supernovae Ia redshift data with a single parameter, the Hubble constant $H_0$, than the…

General Physics · Physics 2018-10-31 Rajendra P. Gupta

We review the use of Type Ia supernovae for cosmological distance determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that (a) the Hubble expansion is linear, (b) H_0 = 65 +/- 2 (statistical) km/s/Mpc, (c) the bulk motion of the Local…

Astrophysics · Physics 2007-05-23 A. V. Filippenko , A. G. Riess

By using the supernovae type Ia data we study influence of the anisotropy (although low) on the evolution of the universe and compare ${\Lambda}$CDM model with 6 representative parametrizations of the recent Hubble expansion history $H(z)$.…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 H. Hossienkhani , H. Yousefi , N. Azimi

In this paper, by considering an absorption probability independent of photon wavelength, we show that current type Ia supernovae (SNe Ia) and gamma ray burst (GRBs) observations plus high-redshift measurements of the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 R. F. L. Holanda , S. H. Pereira , Deepak Jain

It is well known that the Milgrom's MOND (modified Newtonian dynamics) explains well the mass discrepancy problem in galaxy rotation curves. The MOND predicts a universal acceleration scale below which the Newtonian dynamics is invalid yet.…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-26 Yong Zhou , Zhi-Chao Zhao , Zhe Chang

A recent study of the rotation of the plane of polarization of light from 160 cosmological sources claims to find significant evidence for cosmological anisotropy. We point out methodological weaknesses of that study, and reanalyze the same…

Astrophysics · Physics 2009-12-30 Thomas J. Loredo , Eanna E. Flanagan , Ira M. Wasserman

We use Pantheon Type Ia supernova (SN Ia) apparent magnitude, DES-3yr binned SN Ia apparent magnitude, Hubble parameter, and baryon acoustic oscillation measurements to constrain six spatially flat and non-flat cosmological models. These…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Shulei Cao , Joseph Ryan , Bharat Ratra

Parameters that quantify the acceleration of cosmic expansion are conventionally determined within the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) model, which fixes spatial curvature to be homogeneous. Generic averages of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Lawrence H. Dam , Asta Heinesen , David L. Wiltshire

Type Ia Supernovae (SNe Ia) are widely used to measure the expansion of the Universe. To perform such measurements the luminosity and cosmological redshift ($z$) of the SNe Ia have to be determined. The uncertainty on $z$ includes an…

We investigate the possibility of measuring the Hubble constant, the fractional energy density components and the equation of state parameter of the ``dark energy'' using lensed multiple images of high-redshift supernovae. With future…

Astrophysics · Physics 2009-11-07 A. Goobar , E. Mortsell , R. Amanullah , P. Nugent

The observational behavior of spherically symmetric inhomogeneous cosmological models is studied, which consist of inner and outer homogeneous regions connected by a shell or an intermediate self-similar region. It is assumed that the…

Astrophysics · Physics 2009-10-31 Kenji Tomita

We perform a number of inter-related cosmographic fits to the legacy05 and gold06 supernova datasets. We pay particular attention to the influence of both statistical and systematic uncertainties, and also to the extent to which the choice…

General Relativity and Quantum Cosmology · Physics 2007-07-31 Celine Cattoen , Matt Visser