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The B-modes of polarization at frequencies ranging from 50-1000 GHz are produced by Galactic dust, lensing of primordial E-modes in the cosmic microwave background (CMB) by intervening large scale structure, and possibly by primordial…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Jason Poh , Scott Dodelson

Scaling networks of cosmic defects, such as strings and textures, actively generate scalar, vector and tensor metric perturbations throughout the history of the universe. In particular, {\em vector} modes sourced by defects are an efficient…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Adam Moss , Levon Pogosian

We compute the bispectrum induced in the cosmic microwave background (CMB) temperature and polarisation by the evolution of the primordial density perturbations using the second-order Boltzmann code SONG. We show that adding polarisation…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-03 Guido W. Pettinari , Christian Fidler , Robert Crittenden , Kazuya Koyama , Antony Lewis , David Wands

Within cosmological perturbation theory, the cosmic microwave background anisotropies are usually computed from a Boltzmann hierarchy coupled to the perturbed Einstein equations. In this setup, one set of multipoles describes the…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Cyril Pitrou , Thiago S. Pereira , Julien Lesgourgues

We study several anisotropic inflationary models and their implications for the observed violation of statistical isotropy in the CMBR data. In two of these models the anisotropy decays very quickly during the inflationary phase of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Pranati K. Rath , Tanmay Mudholkar , Pankaj Jain , Pavan K. Aluri , Sukanta Panda

Precise polarisation measurements of the cosmic microwave background (CMB) require accurate knowledge of the instrument orientation relative to the sky frame used to define the cosmological Stokes parameters. Suitable celestial calibration…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-09 M. H. Abitbol , J. C. Hill , B. R. Johnson

The network of cosmic strings generated in a phase transition during inflation enters the scaling regime later than that of usual strings. If it occurs after the recombination, temperature anisotropies of the cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-23 Kohei Kamada , Yuhei Miyamoto , Daisuke Yamauchi , Jun'ichi Yokoyama

The COBE satellite has discovered anisotropies in the cosmic microwave background (CMB) consistent with a scale invariant spectrum of density perturbations. As reviewed in this lecture, topological defect models of structure formation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert H. Brandenberger

We show that a one-component variable-emissivity-spectral-index model (the free-{\alpha} model) provides more physically motivated estimates of dust temperature at the Galactic polar caps than one- or two-component…

Astrophysics of Galaxies · Physics 2012-10-24 Z. Liang , D. J. Fixsen , B. Gold

Angular power spectra computed from Planck HFI 353 GHz intensity and polarization maps produce a TB correlation that can be approximated by a power law. Whether the observed TB correlation is an induced systematic feature or a physical…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-17 J. L. Weiland , G. E. Addison , C. L. Bennett , M. Halpern , G. Hinshaw

In this paper, we explore the power of the cosmic microwave background (CMB) polarization (E-mode) data to corroborate four potential anomalies in CMB temperature data: the lack of large angular-scale correlations, the alignment of the…

Since the B-mode polarization of the cosmic microwave background (CMB) was detected by the BICEP2 experiment and an unexpectedly large tensor-to-scalar ratio, $r=0.20^{+0.07}_{-0.05}$, was found, the base standard cosmology should at least…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-22 Jing-Fei Zhang , Yun-He Li , Xin Zhang

Much of modern cosmology relies on the Cosmological Principle, the assumption that the Universe is isotropic and homogeneous on sufficiently large scales, but it remains worthwhile to examine cosmological models that violate this principle…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-01 Ananda F. Smith , Craig J. Copi , Glenn D. Starkman

Analyses of the cosmic microwave background (CMB) radiation maps made by the Wilkinson Microwave Anisotropy Probe (WMAP) have revealed anomalies not predicted by the standard inflationary cosmology. In particular, the power of the…

Earth and Planetary Astrophysics · Physics 2014-11-20 V. Dikarev , O. Preuss , S. Solanki , H. Krueger , A. Krivov

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 investigate which of the exotic Doppler peak features found for textures and cosmic strings are generic novelties pertaining to defects. We find that the ``out of phase'' texture signature is an accident. Generic defects, when they…

Astrophysics · Physics 2007-05-23 Joao Magueijo

We impose constraints on the topology of the Universe determined from a search for matched circles in the cosmic microwave background (CMB) temperature anisotropy patterns of the 7-year WMAP data. We pay special attention to the sensitivity…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-19 P. Bielewicz , A. J. Banday , K. M. Gorski

We present new constraints on gravitational vector perturbations ($\mathcal{V}$-modes) using Cosmic Microwave Background (CMB) data, including temperature and $E$-mode polarization from SPT-3G D1, ACT-DR6, and $Planck$, as well as $B$-mode…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Ali Rida Khalife , Cyril Pitrou

The recent BICEP2 detection of degree scale CMB B-mode polarization, coupled with a deficit of observed power in large angle temperature anisotropy, suggest that the slow-roll parameter $\epsilon_H$, the fractional variation in the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Wayne Hu