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Related papers: Testing Isotropy in the Local Universe

200 papers

Line intensity mapping (LIM) proposes to efficiently observe distant faint galaxies and map the matter density field at high redshift. Building upon the formalism in the companion paper, we first highlight the degeneracies between cosmology…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-29 Emmanuel Schaan , Martin White

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. We have developed a new method for calculating the CMB anisotropy in…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Dmitry Pogosyan , J. Richard Bond

We have used the Union2.1 SNIa compilation to search for possible Hubble expansion anisotropies, dividing the sky in 9 solid angles containing roughly the same number of SNIa, as well as in the two Galactic hemispheres. We identified only…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-09 K. Migkas , M. Plionis

We investigate distributional properties of a class of spectral spatial statistics under irregular sampling of a random field that is defined on $\mathbb{R}^d$, and use this to obtain a test for isotropy. Within this context, edge effects…

Statistics Theory · Mathematics 2024-01-17 Theresa Eckle , Anne van Delft , Holger Dette

The cosmological principle, as the cornerstone of the standard cosmological model, requires that the Universe be homogeneous and isotropic on large scales. As a fundamental assumption, it is constantly subjected to testing via various…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Jianping Hu , Chao Geng , Xuandong Jia , Zhaoyu Zuo , Taozhi Yang , Fayin Wang

Obtaining accurately calibrated redshift distributions of photometric samples is one of the great challenges in photometric surveys like LSST, Euclid, HSC, KiDS, and DES. We present an inference methodology that combines the redshift…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-09 M. M. Rau , C. B. Morrison , S. J. Schmidt , S. Wilson , R. Mandelbaum , Y. Y. Mao

We investigate the `Local Hole', an anomalous under-density in the local galaxy environment, by extending our previous galaxy $K-$band number-redshift and number-magnitude counts to $\approx 90\%$ of the sky. Our redshift samples are taken…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-09 Jonathan H. W. Wong , T. Shanks , N. Metcalfe , J. R. Whitbourn

There have recently been several claims of an asymmetric distribution of large scale fluctuations in the WMAP data. I review some recent results from a test of isotropy of the power spectrum at all scales and show how the power is…

Astrophysics · Physics 2007-05-23 F. K. Hansen

We study cosmic variance in deep high redshift surveys and its influence on the determination of the luminosity function for high redshift galaxies. For several survey geometries relevant for HST and JWST instruments, we characterize the…

Astrophysics · Physics 2020-07-28 M. Trenti , M. Stiavelli

We probe the statistical isotropy hypothesis of the large-scale structure with the second Planck Sunyaev-Zeldovich (PSZ2) galaxy clusters data set. Our analysis adopts a statistical-geometrical method which compares the 2-point angular…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-15 C. A. P. Bengaly , A. Bernui , I. S. Ferreira , J. S. Alcaniz

Calibrating the photometric redshifts of >10^9 galaxies for upcoming weak lensing cosmology experiments is a major challenge for the astrophysics community. The path to obtaining the required spectroscopic redshifts for training and…

The assumption of homogeneity and isotropy on large scales is one of the main hypotheses of the standard cosmological model. In this paper, we revisit a test of cosmological isotropy using type Ia supernova (SN Ia) distances provided by the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-01 Uendert Andrade , Carlos A. P. Bengaly , Beethoven Santos , Jailson S. Alcaniz

Traditional photometric redshift methods use only color information about the objects in question to estimate their redshifts. This paper introduces a new method utilizing colors, luminosity, surface brightness, and radial light profile to…

Astrophysics · Physics 2008-11-26 James J. Wray , James E. Gunn

By using high-resolution and deep Ks band observations of early-type galaxies of the nearby Universe and of a cluster at z=0.3 we show that the two luminosity functions (LFs) of the local universe derived from 2MASS data miss a fair…

Astrophysics · Physics 2009-11-07 S. Andreon

Recently a symmetry-based method to test for statistical isotropy of the cosmic microwave background was developed. We apply the method to template-cleaned 3-year and 5-year WMAP-$DA$ maps. We examine a wide range of angular multipoles from…

Astrophysics · Physics 2010-11-02 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

Galaxy surveys probe both structure formation and the expansion rate, making them promising avenues for understanding the dark universe. Photometric surveys accurately map the 2D distribution of galaxy positions and shapes in a given…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-19 Samuel Passaglia , Alessandro Manzotti , Scott Dodelson

We study galaxy evolution and spatial patterns in the surroundings of a sample of 2dF groups. Our aim is to find evidence of galaxy evolution and clustering out to 10 times the virial radius of the groups and so redefine their properties…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. L. B. Ribeiro , M. Trevisan , P. A. A. Lopes , A. C. Schilling

We describe the classical cosmological tests, such as the Log$N$-Log$S$, redshift-magnitude and angular diameter tests, and propose some new tests of the evolution of galaxies and the universe. Most analyses of these tests treat the problem…

Astrophysics · Physics 2009-10-30 Vahe' Petrosian

When searching for deviations of statistical isotropy in CMB, a popular strategy is to write the two-point correlation function (2pcf) as the most general function of four spherical angles (i.e., two unit vectors) in the celestial sphere.…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-12 Andre L. Froes , Thiago S. Pereira , Armando Bernui , Glenn D. Starkman