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Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with steerable wavelets on the sphere. Firstly,…

天体物理学 · 物理学 2009-09-29 P. Vielva , Y. Wiaux , E. Martinez-Gonzalez , P. Vandergheynst

Noticeable deviations from the prediction of the fiducial LCDM cosmology are found in the angular power spectrum of the CMB. Besides large-angle anomalies, the WMAP 1st year data revealed a dip in the power spectrum at l \sim 200, which…

宇宙学与河外天体物理 · 物理学 2011-05-12 Amanda Yoho , Francesc Ferrer , Glenn D. Starkman

Wilkinson Microwave Anisotropy Probe (WMAP) has provided us with the yet highest resolution all-sky maps of the Cosmic Microwave Background. As a result of thermal Sunyaev-Zel'dovich effect, clusters of galaxies are imprinted as tiny,…

天体物理学 · 物理学 2009-11-11 Niayesh Afshordi

The new three year WMAP data seem to confirm the presence of non-standard large scale features in the Cosmic Microwave Anisotropies power spectrum. While these features may hint at uncorrected experimental systematics, it is also possible…

天体物理学 · 物理学 2009-11-11 Laura Covi , Jan Hamann , Alessandro Melchiorri , Anze Slosar , Irene Sorbera

We test the hypothesis that the temperature of the cosmic microwave background is consistent with a Gaussian random field defined on the celestial sphere, using de-biased internal linear combination (DILC) map produced from the 3-year WMAP…

天体物理学 · 物理学 2010-11-11 Lung-Yih Chiang , Pavel D. Naselsky , Peter Coles

Sky temperature map of the cosmic microwave background (CMB) is one of the premier probes of cosmology. To minimize instrumentally induced systematic errors, CMB anisotropy experiments measure temperature differences across the sky using…

天体物理学 · 物理学 2008-06-30 Hao Liu , Ti-Pei Li

The Wilkinson Microwave Anisotropy Probe (WMAP) has measured lower amplitudes for the temperature quadrupole and octopole anisotropies than expected in the best fitting (concordance) Lambda-dominated cold dark matter cosmology. Some authors…

天体物理学 · 物理学 2009-11-10 G. Efstathiou

The implications of the WMAP (Wilkinson Microwave Anisotropy Probe) third year data for inflation are investigated using both the slow-roll approximation and an exact numerical integration of the inflationary power spectra including a…

天体物理学 · 物理学 2009-11-11 Jerome Martin , Christophe Ringeval

The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or foregrounds. An…

宇宙学与河外天体物理 · 物理学 2012-11-01 M. Hansen , J. Kim , A. M. Frejsel , S. Ramazanov , P. Naselsky , W. Zhao , C. Burigana

The Wilkinson Microwave Anisotropy Probe WMAP has mapped the entire sky in five frequency bands between 23 and 94 GHz with polarization sensitive radiometers. We present three-year full-sky maps of the polarization and analyze them for…

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the…

天体物理学 · 物理学 2007-05-23 Y. Wiaux , P. Vielva , E. Martinez-Gonzalez , P. Vandergheynst

Since this is a meeting on inflation the title of this talk should probably have been ``The cosmos as a lab for inflation''. I will illustrate how, by combining WMAP observations of the cosmic microwave background (CMB) with smaller scales…

天体物理学 · 物理学 2007-05-23 Licia verde

We consider the hypothesis that nonlocal, omnidirectional, causally-coherent quantum entanglement of inflationary horizons may account for some well-known measured anomalies of Cosmic Microwave Background (CMB) anisotropy on large angular…

广义相对论与量子宇宙学 · 物理学 2022-02-16 Craig Hogan , Stephan S. Meyer

A detection or nondetection of primordial non-Gaussianity in the CMB data is essential not only to test alternative models of the physics of the early universe but also to discriminate among classes of inflationary models. Given this far…

宇宙学与河外天体物理 · 物理学 2010-09-15 A. Bernui , M. J. Reboucas

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…

天体物理学 · 物理学 2008-11-26 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

Given an arbitrary function, we may construct symmetric and antisymmetric functions under a certain operation. Since statistical isotropy and homogeneity of our Universe has been a fundamental assumption of modern cosmology, we do not…

宇宙学与河外天体物理 · 物理学 2012-08-23 Jaiseung Kim , Pavel Naselsky , Martin Hansen

We present a Gaussianity analysis of the WMAP 5-year Cosmic Microwave Background (CMB) temperature anisotropy data maps. We use several third order estimators based on the spherical Mexican hat wavelet. We impose constraints on the local…

天体物理学 · 物理学 2010-11-02 A. Curto , E. Martinez-Gonzalez , P. Mukherjee , R. B. Barreiro , F. K. Hansen , M. Liguori , S. Matarrese

Several unexpected features are observed at large angular scales in the CMB temperature anisotropy measurements by both WMAP and Planck. These include the lack of both variance and correlation, alignment of the lowest multipole moments with…

宇宙学与河外天体物理 · 物理学 2018-07-25 Jessica Muir , Saroj Adhikari , Dragan Huterer

We present the angular power spectrum derived from the first-year Wilkinson Microwave Anisotropy Probe (WMAP) sky maps. We study a variety of power spectrum estimation methods and data combinations and demonstrate that the results are…

There is currently a debate over the existence of claimed statistical anomalies in the cosmic microwave background (CMB), recently confirmed in Planck data. Recent work has focussed on methods for measuring statistical significance, on…

宇宙学与河外天体物理 · 物理学 2015-06-15 A. Rassat , J. -L. Starck