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Related papers: Cosmological Birefringence and the Microwave Backg…

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In the standard cosmological model, the temperature anisotropy of the cosmic microwave background is interpreted as variation in the gravitational potential at the point of emission, due to the emitter being embedded in a region ${\cal C}$…

Astrophysics · Physics 2007-05-23 Richard Lieu

We explore the hemispherical asymmetry predicted in cosmic microwave background polarization when there is an asymmetry in temperature anisotropies due to primordial perturbations. We consider the cases of asymmetries due to adiabatic and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. H. Namjoo , A. A. Abolhasani , H. Assadullahi , S. Baghram , H. Firouzjahi , D. Wands

This article investigates the non-linear evolution of cosmological perturbations on sub-Hubble scales in order to evaluate the unavoidable deviations from Gaussianity that arise from the non-linear dynamics. It shows that the dominant…

Astrophysics · Physics 2009-02-23 Cyril Pitrou , Jean-Philippe Uzan , Francis Bernardeau

Cosmological Birefringence (CB), a rotation of the polarization plane of radiation coming to us from distant astrophysical sources, may reveal parity violation in either the electromagnetic or gravitational sectors of the fundamental…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Amit P. S. Yadav , Meir Shimon , Brian G. Keating

Cosmic microwave background (CMB) anisotropies probe the primordial density field at the edge of the observable Universe. There is a limiting precision (``cosmic variance'') with which anisotropies can determine the amplitude of primordial…

Astrophysics · Physics 2016-08-25 Marc Kamionkowski , Abraham Loeb

The anisotropies in the cosmic microwave background (CMB) provide our best laboratory for testing models of the formation and evolution of large-scale structure. The rich features in the cosmic microwave background anisotropy spectrum, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Zhen Pan , Lloyd Knox , Martin White

We update the limit from the 90 GHz PIQUE ground-based polarimeter on the magnitude of any polarized anisotropy of the cosmic microwave radiation. With a second year of data, we have now limited both Q and U on a ring of 1 degree radius.…

Astrophysics · Physics 2009-11-07 M. M. Hedman , D. Barkats , J. O. Gundersen , J. J. McMahon , S. T. Staggs , B. Winstein

We examine the constraints cosmological observations can place on any trans-Planckian corrections to the primordial spectrum of perturbations underlying the anisotropies in the Cosmic Microwave Background. We focus on models of…

Astrophysics · Physics 2011-05-12 Richard Easther , William H Kinney , Hiranya Peiris

If current ideas about unified field theories are correct, macroscopic cosmic defects may well exist. The observation of such an entity would have enormous significance for our understanding of fundamental physics. This paper points out a…

Astrophysics · Physics 2009-10-28 Neil Turok

We discuss the influence of gravitational waves (GWs) upon the polarisation of the Cosmic Microwave Background Radiation (CMBR). We show how to compute the {\em rms} temperature anisotropy and polarisation of the CMBR induced by GWs of…

Astrophysics · Physics 2016-06-08 R. A. Frewin , A. G. Polnarev , P. Coles

The cosmic microwave background (CMB), the relic radiation from the early Universe, offers a unique window into both primordial conditions and the intervening large-scale structure (LSS) it traverses. Interactions between CMB photons and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Federico Bianchini , Abhishek S. Maniyar

Cosmic birefringence is the in-vacuo rotation of the linear polarization plane experienced by photons of the Cosmic Microwave Background (CMB) radiation when theoretically well-motivated parity-violating extensions of Maxwell…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-24 Alessandro Greco , Nicola Bartolo , Alessandro Gruppuso

The cosmic microwave background radiation provides unique constraints on cosmological models. In this Letter we present a summary of the spatial properties of the cosmic microwave background radiation based on the full 4 years of COBE DMR…

Anisotropies in the temperature of the cosmic microwave background have been detected on a range of scales by several different experiments. These anisotropies reflect the primordial spectrum of metric perturbations in the early universe.…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Arthur Kosowsky

The study of anisotropies in the Cosmic Microwave Background radiation is progressing at a phenomenal rate, both experimentally and theoretically. These anisotropies can teach us an enormous amount about the way that fluctuations were…

Astrophysics · Physics 2008-11-26 Douglas Scott , Martin White

We implement the theory of resonant scattering in the context of Cosmic Microwave Background (CMB) polarisation anisotropies. We compute the changes in the E-mode polarisation (EE) and Temperature E-mode (TE) CMB power spectra introduced by…

Astrophysics · Physics 2007-05-23 C. Hernandez-Monteagudo , J. A. Rubino-Martin , R. A. Sunyaev

The Standard Inflationary model predicts an isotropic distribution of the Cosmic Microwave Background temperature fluctuations. Detection of deviations from statistical isotropy would call for a revision of the physics of the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Laura Cayon

We have studied the cosmic microwave background (CMB) map looking for features beyond cosmological isotropy. We began by tiling the CMB variance map (which are produced by different smoothing scales) with stripes of different sizes along…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-12 MohammadHossein Jamshidi , Abdolali Banihashemi , Nima Khosravi

We review the theory of the temperature anisotropy and polarization of the cosmic microwave background (CMB) radiation, and describe what we have learned from current CMB observations. In particular, we discuss how the CMB is being used to…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-22 Anthony Challinor , Hiranya Peiris

The V-mode polarization of the Cosmic Microwave Background is discussed in a weakly magnetized plasma. The VV and VT angular power spectra are computed for adiabatic initial conditions of the Einstein-Boltzmann hierarchy. Depending upon the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Massimo Giovannini
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