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We describe a new map-making code for cosmic microwave background (CMB) observations. It implements fast algorithms for convolution and transpose convolution of two functions on the sphere (Wandelt & G\'{o}rski 2001). Our code can account…

天体物理学 · 物理学 2009-11-10 Charmaine Armitage , Benjamin D. Wandelt

A previous work (Monteser\'in et al. 2008) estimated the CMB variance from the three-year WMAP data, finding a lower value than expected from Gaussian simulations using the WMAP best-fit cosmological model. We repeat the analysis on the…

宇宙学与河外天体物理 · 物理学 2015-05-18 M. Cruz , P. Vielva , E. Martínez-González , R. B. Barreiro

Multiply connected space sections of the universe on a scale smaller than the horizon size can leave an imprint on cosmic microwave background polarization maps, in such a way that the so-called ``circles-in-the-sky'' method can be used to…

天体物理学 · 物理学 2007-05-23 Alain Riazuelo , Samuel Caillerie , Marc Lachièze-Rey , Roland Lehoucq , Jean-Pierre Luminet

We extend the previously described CMB Gibbs sampling framework to allow for exact Bayesian analysis of anisotropic universe models, and apply this method to the 5-year WMAP temperature observations. This involves adding support for…

天体物理学 · 物理学 2011-02-11 Nicolaas E. Groeneboom , Hans Kristian Eriksen

Recent observations have pointed out various anomalies in some multipoles (small $\ell $) of the cosmic microwave background (CMB). In this paper, it is proved that some of these anomalies could be explained in the framework of a modified…

天体物理学 · 物理学 2009-11-13 J. A. Morales , D. Sáez

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

宇宙学与河外天体物理 · 物理学 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

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

Conformal cyclic cosmology (CCC) posits the existence of an aeon preceding our Big Bang 'B', whose conformal infinity 'I' is identified, conformally, with 'B', now regarded as a spacelike 3-surface. Black-hole encounters, within bound…

宇宙学与河外天体物理 · 物理学 2010-11-18 V. G. Gurzadyan , R. Penrose

We explore the low-l likelihood of the angular spectrum C(l) of masked CMB temperature maps using an adaptive importance sampler. We find that, in spite of a partial sky coverage, the likelihood distribution of each C(l) closely follows an…

宇宙学与河外天体物理 · 物理学 2015-05-13 K. Benabed , J. -F. Cardoso , S. Prunet , E. Hivon

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck…

宇宙学与河外天体物理 · 物理学 2025-09-05 Laura Herold , Graeme E. Addison , Charles L. Bennett , Hayley C. Nofi , J. L. Weiland

Recent observations suggest that there are violations of the isotropy of the universe at large scales, an important part of the cosmological principle. In this paper, we use the Cosmic Microwave Background (CMB) data to search for spatial…

宇宙学与河外天体物理 · 物理学 2022-04-20 Shek Yeung , Ming-Chung Chu

Large patterns could exist on the microwave sky as a result of various non-standard possibilities for the large-scale Universe -- rotation or shear, non-trivial topology, and single topological defects are specific examples. All-sky (or…

天体物理学 · 物理学 2009-10-31 Emory F. Bunn , Douglas Scott

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

天体物理学 · 物理学 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

We examine all-sky cosmic microwave background (CMB) temperature maps on large angular scales to compare their consistency with two scenarios: the standard inflationary quantum picture, and a distribution constrained to have a universal…

宇宙学与河外天体物理 · 物理学 2022-04-13 Nathaniel Selub , Frederick Wehlen , Craig Hogan , Stephan S. Meyer

The motion of our solar system relative to the CMB rest frame leads to subtle distortions in the observed CMB sky map due to the aberration effect. Usually the corresponding peculiar velocity is determined from the CMB dipole but neglecting…

宇宙学与河外天体物理 · 物理学 2021-07-30 Ralf Aurich , David Reinhardt

The presence of matter in the path of relic photons causes distortions in the angular pattern of the cosmic microwave background (CMB) temperature fluctuations, modifying their properties in a slight but measurable way. Recently, the Planck…

宇宙学与河外天体物理 · 物理学 2017-09-11 G. A. Marques , C. P. Novaes , A. Bernui , I. S. Ferreira

It has been recently realized (Rephaeli 1995) that the relativistic corrections to the spectral distortions of the cosmic microwave background (CMB) measured in the direction of clusters of galaxies containing hot gas are significant and…

天体物理学 · 物理学 2007-05-23 S. Y. Sazonov , R. A. Sunyaev

Recent observations have indicated a Cosmic Microwave Background (CMB) temperature decrement in the direction of local galaxies within the 2MASS Redshift Survey. We investigate this detection by analyzing its frequency dependence and…

宇宙学与河外天体物理 · 物理学 2025-06-06 M. Cruz , E. Martínez-González , C. Gimeno-Amo , B. J. Kavanagh , M. Tucci

We use an optimal estimator to study the variance of the WMAP 9 CMB field at low resolution, in both temperature and polarization. Employing realistic Monte Carlo simulation, we find statistically significant deviations from the…

宇宙学与河外天体物理 · 物理学 2015-06-15 A. Gruppuso , P. Natoli , F. Paci , F. Finelli , D. Molinari , A. De Rosa , N. Mandolesi

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