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Related papers: Polarized Spots in Anisotropic Open Universes

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Statistical Isotropy of the Cosmic Microwave Background (CMB) radiation has been studied and debated extensively in recent years. Under this assumption, the hot spots and cold spots of the CMB are expected to be uniformly distributed over a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-14 Md Ishaque Khan , Rajib Saha

The polarization of the CMB offers a potentially valuable probe of the physics of the early universe, specifically of the velocity of the photon-baryon fluid on the last scattering surface. Here we discuss qualitatively the correlations…

Astrophysics · Physics 2007-05-23 Robert Crittenden

Many of the current anomalies reported in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-year data disappear after `correcting' for the best-fit embedded Bianchi type VII_h component (Jaffe et al. 2005), albeit assuming no dark energy…

Astrophysics · Physics 2009-09-29 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

We have extended the analysis of Jaffe et al. to a complete Markov chain Monte Carlo (MCMC) study of the Bianchi type ${\rm VII_h}$ models including a dark energy density, using 1-year and 3-year Wilkinson Microwave Anisotropy Probe (WMAP)…

Astrophysics · Physics 2008-11-26 M. Bridges , J. D. McEwen , A. N. Lasenby , M. P. Hobson

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530,…

The report of a significant deviation of the CMB temperature anisotropies distribution from Gaussianity (soon after the public release of the WMAP data in 2003) has become one of the most solid WMAP anomalies. This detection grounds on an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 P. Vielva

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…

Astrophysics · Physics 2008-06-30 Hao Liu , Ti-Pei Li

We develop the formalism necessary to study four-point functions of the cosmic microwave background (CMB) temperature and polarization fields. We determine the general form of CMB trispectra, with the constraints imposed by the assumption…

Astrophysics · Physics 2011-05-12 Takemi Okamoto , Wayne Hu

In the present work, we study the largest structures of the CMB temperature measured by Planck in terms of the most prominent peaks on the sky, which, in particular, are located in the southern galactic hemisphere. Besides these large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 A. Marcos-Caballero , E. Martínez-González , P. Vielva

The plane-mirror symmetry previously noticed in the Cosmic Microwave Background (CMB) temperature anisotropy maps of Wilkinson Microwave Anisotropy Probe is shown to possess certain anomalous properties. The degree of the randomness…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 V. G. Gurzadyan , T. Ghahramanyan , A. L. Kashin , H. G. Khachatryan , A. A. Kocharyan , H. Kuloghlian , D. Vetrugno , G. Yegorian

All-sky maps of the cosmic microwave background temperature fluctuations are usually represented by a spherical harmonic decomposition involving modes labelled by their degree l and order m (where -l < m < +l). The zonal modes (i.e those…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Jo Short , Peter Coles

Many weak lensing calculations make use of the Born approximation where the light ray is approximated by a straight path. We examine the effect of Born-corrections for lensing of the cosmic microwave background in an analytical approach by…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Steffen Hagstotz , Björn Malte Schäfer , Philipp M. Merkel

One of the most intriguing hints of a departure from the standard cosmological model is a large-scale dipolar power asymmetry in the cosmic microwave background (CMB). If not a statistical fluke, its origins must lie in the modulation of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 J. P. Zibin , D. Contreras

The standard $\Lambda$CDM model has been highly successful in describing cosmic microwave background (CMB) observations. Nevertheless, a set of large-scale statistical anomalies persists in temperature anisotropies across WMAP and Planck.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Jiazheng Dou , Wen Zhao

We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically…

Astrophysics · Physics 2008-11-26 Xuelei Chen , Marc Kamionkowski

We present the full set of power spectra of cosmic microwave background (CMB) temperature and polarization anisotropies due to the coupling between quintessence and pseudoscalar of electromagnetism. This coupling induces the rotation of the…

Astrophysics · Physics 2009-11-11 Guo-Chin Liu , Seokcheon Lee , Kin-Wang Ng

Recent measurements of the temperature field of Cosmic Microwave Background (CMB) provide tantalising evidence for violation of Statistical Isotropy (SI) that constitutes a fundamental tenet of contemporary cosmology. CMB space based…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Suvodip Mukherjee , Tarun Souradeep

We present a Gaussianity test of the cosmic microwave background (CMB) polarization by analyzing the statistics of unpolarized points in the sky, classified into three distinct types: saddles, comets, and beaks. This classification of…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 K. O. Parfenov , D. I. Novikov , A. O. Mihalchenko

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

Two-point correlation functions of cosmic microwave background polarization provide a physically independent probe of the surprising suppression of correlations in the cosmic microwave background temperature anisotropies at large angular…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Amanda Yoho , Simone Aiola , Craig J. Copi , Arthur Kosowsky , Glenn D. Starkman