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We report measurements of anisotropy in the cosmic microwave background radiation over the multipole range l ~ 200 - 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power…

There has been growing interest in the possibility of testing more precisely the assumption of statistical isotropy of primordial density perturbations. If it is to be tested with galaxy surveys at distance scales <~ 10 Mpc, then nonlinear…

Astrophysics · Physics 2008-11-26 Shin'ichiro Ando , Marc Kamionkowski

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…

Astrophysics · Physics 2009-09-29 Christopher O'Dell

We predict that neutrino sources following the matter distribution of the universe result in an anisotropy in the neutrino sky imprinted by the local large-scale structure. We calculate the level of this anisotropy and explore how it…

High Energy Astrophysical Phenomena · Physics 2025-11-13 Marco Stein Muzio , Noémie Globus

We perform a detailed analysis on a primordial gravitational-wave background amplified during a Kasner-like pre-inflationary phase allowing for general triaxial anisotropies. It is found that the predicted angular distribution map of…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 Yu Furuya , Yuki Niiyama , Yuuiti Sendouda

We show that the anisotropies of the astrophysical stochastic gravitational wave background in the mHz band have a strong dependence on the modelling of galactic and sub-galactic physics. We explore a wide range of self-consistent…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Giulia Cusin , Irina Dvorkin , Cyril Pitrou , Jean-Philippe Uzan

We calculate the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.64 10^{-2}$, we find $\Delta T_{pol}/ T_0…

Astrophysics · Physics 2007-10-24 Paolo Cea

The anisotropies in the cosmic microwave background (CMB) provide our best laboratory for testing models of the formation and evolution of large-scale structure. The rich features in the cosmic microwave background anisotropy spectrum, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Zhen Pan , Lloyd Knox , Martin White

We introduce new symmetry-based methods to test for isotropy in cosmic microwave background radiation. Each angular multipole is factored into unique products of power eigenvectors, related multipoles and singular values that provide 2 new…

Astrophysics · Physics 2008-11-26 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

We study the complex visibilities of the cosmic microwave background anisotropies that are observables in interferometric observations of the cosmic microwave background, using the multipole expansion methods commonly adopted in analyzing…

Astrophysics · Physics 2009-12-31 Kin-Wang Ng

Recent estimates of cosmological parameters derived from Cosmic Microwave Background (CMB) anisotropies are based on the assumption that we know the precise amount of energy density in relativistic particles in the universe, $\omega_{rel}$,…

Astrophysics · Physics 2008-11-26 R. Bowen , S. H. Hansen , A. Melchiorri , J. Silk , R. Trotta

We develop and examine the principles governing the formation of distortions in the cosmic microwave background. Distortions in the frequency or spectral distribution of the background probe the thermal history of the universe whereas those…

Astrophysics · Physics 2009-07-17 Wayne Hu

Extensive, accurate imaging of the Cosmic Background Radiation temperature anisotropy at sub--degree angular resolution is widely recognized as one of the most crucial goals for cosmology and astroparticle physics in the next decade. We…

Astrophysics · Physics 2016-08-30 L. Danese , L. Toffolatti , A. Franceschini , M. Bersanelli , N. Mandolesi

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

Probing the geometry of the universe is one of the most important endevours in cosmology. Current observational data from the Cosmic Microwave Background anisotropy (CMB), galaxy surveys and type Ia supernovae (SNe Ia) strongly constrain…

Astrophysics · Physics 2008-12-18 Laura Mersini-Houghton , Yun Wang , Pia Mukherjee , Ervin Kafexhiu

A new method is proposed for modelling spherically symmetric inhomogeneities in the Universe. The inhomogeneities have finite size and are compensated, so they do not exert any measurable gravitational force beyond their boundary. The…

Astrophysics · Physics 2009-10-31 A. N. Lasenby , C. J. L. Doran , M. P. Hobson , Y. Dabrowski , A. D. Challinor

I explain the origin and evolution of anisotropies in the Cosmic Microwave Background (CMB) and argue that upcoming experiments will measure cosmological and fundamental parameters very accurately. Most of the paper focuses on present data,…

High Energy Physics - Phenomenology · Physics 2014-11-17 Scott Dodelson

Unresolved and resolved sources of gravitational waves are at the origin of a stochastic gravitational wave background. While the computation of its mean density as a function of frequency in a homogeneous and isotropic universe is standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-19 Giulia Cusin , Cyril Pitrou , Jean-Philippe Uzan

A new method arising from a gauge-theoretic approach to general relativity is applied to the formation of clusters in an expanding universe. The three cosmological models (Omega_0=1, Omega_Lambda=0), (Omega_0=0.3, Omega_Lambda=0.7),…

Astrophysics · Physics 2015-06-24 Y. Dabrowski , M. J. Hall , I. L. Sawicki , A. N. Lasenby

We propose to use a simple observable, the fractional area of "hot spots" in weak lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-shear regions are directly…

Astrophysics · Physics 2008-09-24 Sheng Wang , Zoltan Haiman , Morgan May , John Kehayias
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