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Related papers: Polarized Spots in Anisotropic Open Universes

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We study the coherent temperature and polarization patterns produced in homogeneous but anisotropic cosmological models. We show results for all Bianchi types with a Friedman-Robertson-Walker limit (i.e. Types I, V, VII$_{0}$, VII$_{h}$ and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Rockhee Sung , Peter Coles

Combining a recent derivation of the CMB evolution equations for homogeneous but anisotropic (Bianchi) cosmologies with an account of the full linearized dynamical freedoms available in such models, I calculate and discuss the various…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-30 Andrew Pontzen

We have returned to our previous Bianchi VII_h analysis in light of the Cruz et al. 2007 suggestion that the cold spot observed near the southern Galactic pole may be a remnant temperature perturbation of a cosmic texture. In Bridges et al.…

We consider the issue of characterizing the coherent large-scale patterns from CMB temperature maps in globally anisotropic cosmologies. The methods we investigate are reasonably general; the particular models we test them on are the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Rockhee Sung , Jo Short , Peter Coles

We derive the CMB radiative transfer equation in the form of a multipole hierarchy in the nearly-Friedmann-Robertson-Walker limit of homogeneous, but anisotropic, universes classified via their Bianchi type. Compared with previous…

Astrophysics · Physics 2007-09-13 Andrew Pontzen , Anthony Challinor

We test the asymmetry of the Cosmic Microwave Background anisotropy jointly in temperature and polarization. We study the hemispherical asymmetry, previously found only in the temperature field, with respect to the axis identified by Hansen…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-13 F. Paci , A. Gruppuso , F. Finelli , P. Cabella , A. De Rosa , N. Mandolesi , P. Natoli

We study the polarization-polarization and polarization-temperature correlations in standard adiabatic scenarios for structure formation. Temperature anisotropies due to gravitational potential wells and oscillations in the…

Astrophysics · Physics 2009-10-22 David Coulson , Robert G. Crittenden , Neil Turok

Radiation which has a quadrupole component of anisotropy, can get polarized by Thomson scattering from charged particles. In the cosmological context, the microwave background photons develop significant quadrupole anisotropy as they free…

Astrophysics · Physics 2009-10-30 T. R. Seshadri , K. Subramanian

We predict the polarization of cosmic microwave background (CMB) photons that results from a cosmic bubble collision. The polarization is purely E-mode, symmetric around the axis pointing towards the collision bubble, and has several…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Bartlomiej Czech , Matthew Kleban , Klaus Larjo , Thomas S. Levi , Kris Sigurdson

We present local extrema studies of two models that introduce a preferred direction into the observed cosmic microwave background (CMB) temperature field. In particular, we make a frequentist comparison of the one- and two-point statistics…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Zhen Hou , A. J. Banday , K. M. Gorski , N. E. Groeneboom , H. K. Eriksen

We examine the degree to which observations of large-scale cosmic microwave background (CMB) polarization can shed light on the puzzling large-scale power modulation in maps of CMB anisotropy. We consider a phenomenological model in which…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Emory F. Bunn , Qingyang Xue , Haoxuan Zheng

The cosmic microwave background (CMB) temperature anisotropies exhibit a large-scale dipolar power asymmetry. To determine whether this is due to a real, physical modulation or is simply a large statistical fluctuation requires the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 D. Contreras , J. P. Zibin , D. Scott , A. J. Banday , K. M. Górski

We study contributions from inhomogeneous (patchy) reionization to arcminute scale ($1000 < \ell < 10,000$) cosmic microwave background (CMB) anisotropies. We show that inhomogeneities in the ionization fraction, rather than in the mean…

Astrophysics · Physics 2008-11-26 M. G. Santos , A. Cooray , Z. Haiman , L. Knox , C. -P. Ma

We perform a definitive analysis of Bianchi VII_h cosmologies with WMAP observations of the cosmic microwave background (CMB) temperature anisotropies. Bayesian analysis techniques are developed to study anisotropic cosmologies using…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-04 J. D. McEwen , T. Josset , S. M. Feeney , H. V. Peiris , A. N. Lasenby

We generalize the predictions for the CMB anisotropy patterns arising in Bianchi type VIIh universes to include a dark energy component. We consider these models in light of the result of Jaffe et al. (2005a,b) in which a correlation was…

Astrophysics · Physics 2009-11-13 T. R. Jaffe , S. Hervik , A. J. Banday , K. M. Gorski

Motivated by the success of the Bianchi VII_h model in addressing many of the anomalies observed in the WMAP data (Jaffe et al.), we present calculations in real and in wavelet space of the Higher Criticism statistic of the Bianchi…

Astrophysics · Physics 2009-11-11 L. Cayon , A. J. Banday , T. Jaffe , H. K. Eriksen , F. K. Hansen , K. M. Gorski , J. Jin

Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy…

Astrophysics · Physics 2008-11-26 Tuhin Ghosh , Amir Hajian , Tarun Souradeep

Quantum creation processes during the very rapid early expansion of the universe are believed to give rise to temperature anisotropies and polarization patterns in the CMB radiation. These have been observed by satellites such as COBE,…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Leonard Parker

We present a pedagogical and phenomenological introduction to the study of cosmic microwave background (CMB) polarization to build intuition about the prospects and challenges facing its detection. Thomson scattering of temperature…

Astrophysics · Physics 2009-08-18 Wayne Hu , Martin White

The angular power spectrum of the cosmic microwave background temperature anisotropy observed by WMAP has an anomalous dip at l~20 and bump at l~40. One explanation for this structure is the presence of features in the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-19 Michael J. Mortonson , Cora Dvorkin , Hiranya V. Peiris , Wayne Hu
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