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We examine the redshifts of a comprehensive set of published Type Ia supernovae, and provide a combined, improved catalogue with updated redshifts. We improve on the original catalogues by using the most up-to-date heliocentric redshift…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Anthony Carr , Tamara M. Davis , Daniel Scolnic , Khaled Said , Dillon Brout , Erik R. Peterson , Richard Kessler

Recent high precision measurements of the CMB anisotropies performed by the BOOMERanG and MAXIMA-1 experiments provide an unmatched set of data allowing to probe different cosmological models. Among these scenarios, motivated by the recent…

Astrophysics · Physics 2009-10-31 Philippe Brax , Jerome Martin , Alain Riazuelo

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…

The search for cosmic ray anisotropy has been performed using particles collected by the Alpha Magnetic Spectrometer after the first five years of operation. The positron to electron ratio is consistent with isotropy at all energies and…

High Energy Astrophysical Phenomena · Physics 2016-12-30 G. La Vacca , AMS-02 Collaboration

We present a measurement of the velocity flow of the local universe relative to the CMB rest frame, based on the Jha, Riess & Kirshner (2007) sample of 133 low redshift type Ia supernovae. At a depth of 4500 km/s we find a dipole amplitude…

A new component of the Universe which leads to an accelerated cosmic expansion is found from the measurements of distances to high-redshift type Ia supernovae. We describe the method and the results obtained from the observations of distant…

Astrophysics · Physics 2007-05-23 Bruno Leibundgut , Gertrud Contardo , Patrick Woudt , Jason Spyromilio

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

Astrophysics · Physics 2008-11-26 Tarun Souradeep , Amir Hajian

In this essay, I present an alternative explanation for the cosmic acceleration which appears as a consequence of recent high redshift Supernova data. In the usual interpretation, this cosmic acceleration is explained by the presence of a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. -F. Pascual-Sánchez

Radiation traversing the observable universe provides powerful ways to probe anisotropy of electromagnetic propagation. A controversial recent study claimed a signal of dipole character. Here we test a new and independent data set of 361…

Astrophysics · Physics 2011-09-16 Pankaj Jain , John P. Ralston

There currently exist many observations which are not consistent with the cosmological principle. We review these observations with a particular emphasis on those relevant for Square Kilometre Array (SKA). In particular, several different…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-03 Shamik Ghosh , Pankaj Jain , Gopal Kashyap , Rahul Kothari , Sharvari Nadkarni-Ghosh , Prabhakar Tiwari

With the upcoming sky survey with the Large Synoptic Survey Telescope a great sample of type Ia supernovae will be observed, allowing for a precise mapping of the velocity structure of the universe. Since the source of peculiar velocities…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-21 Io Odderskov , Steen Hannestad

We report recent results from the Pierre Auger Observatory about the study of the anisotropy in the arrival directions of ultra-high energy cosmic rays. We present the results of the search for a dipolar anisotropy at the EeV energy scale.…

High Energy Astrophysical Phenomena · Physics 2019-08-13 J. R. T. de Mello Neto

The origin of small deviations from statistical isotropy in the Cosmic Microwave Background (CMB) - the so-called CMB anomalies - remains an open question in modern cosmology. In this work, we test statistical isotropy in Planck Data…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-09 C. Gimeno-Amo , F. K. Hansen , E. Martínez-González , R. B. Barreiro , A. J. Banday

We propose a Finsler spacetime scenario of the anisotropic universe. The Finslerian universe requires both the fine-structure constant and accelerating cosmic expansion have dipole structure, and the directions of these two dipoles are the…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Xin Li , Hai-Nan Lin , Sai Wang , Zhe Chang

We re-analyze the observed magnitude-redshift relation of type Ia supernovae (SNe Ia) and examine the possibility that the apparent acceleration of the cosmic expansion is not caused by dark energy but is instead a consequence of the…

Astrophysics · Physics 2012-02-03 Masumi Kasai

In this work we derive state-of-the-art model-independent constraints on cosmology from SN Ia by measuring purely kinematical $\left( q,j \right)$ model parameters (where $q$ and $j$ are related to the first and second derivative of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-30 Caroline Heneka

Context.This is the second paper of a series aiming to determine the birth rates of supernovae in the local Universe. Aims. In this paper, we aim to estimate the SN rates in the local universe and fit the delay-time distribution of SNe Ia…

Modern cosmology rests on the cosmological principle, that on large enough scales the Universe is both homogeneous and isotropic. A corollary is that galaxies' spin vectors should be isotropically distributed on the sky. This has been…

Astrophysics of Galaxies · Physics 2025-03-03 Dhruva Patel , Harry Desmond

We examine three SNe Type Ia datasets: Union2.1, JLA and Panstarrs to check their consistency using cosmology blind statistical analyses as well as cosmological parameter fitting. We find that Panstarrs dataset is the most stable of the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Ujjaini Alam , Jeremie Lasue

We study the large-scale anisotropy of the Universe by measuring the dipole in the angular distribution of a flux-limited, all-sky sample of 1.36 million quasars observed by the Wide-field Infrared Survey Explorer (WISE). This sample is…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-01 Nathan Secrest , Sebastian von Hausegger , Mohamed Rameez , Roya Mohayaee , Subir Sarkar , Jacques Colin
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