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Full-sky maps of the cosmic microwave background temperature reveal a 7% asymmetry of fluctuation power between two halves of the sky. A common phenomenological model for this asymmetry is an overall dipole modulation of statistically…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Simone Aiola , Bingjie Wang , Arthur Kosowsky , Tina Kahniashvili , Hassan Firouzjahi

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its…

Following Philcox et al. (2025), we investigate a scenario with a massive partner to the inflaton ($O(100)$ times the inflationary Hubble scale), in which particles are produced during a narrow time period, leaving characteristic hot- or…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-07 Luca H. Abu El-Haj , Oliver H. E. Philcox , J. Colin Hill

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Juan Garcia-Bellido , Ruth Durrer , Elisa Fenu , Daniel G. Figueroa , Martin Kunz

We evaluate the large scale polarization of the cosmic microwave background induced, via Thomson scattering prior to decoupling, by nearly scale-invariant spectra of scalar and tensor metric perturbations, such as those predicted by most…

Astrophysics · Physics 2016-08-30 Diego Harari , Matias Zaldarriaga

For $\pi^0\eta$-photoproduction on the nucleon formal expressions are developed for the five-fold differential cross section and the recoil polarization including beam and target polarizations. The polarization observables are described by…

Nuclear Theory · Physics 2011-02-28 A. Fix , H. Arenhövel

Using dynamical systems theory and a detailed numerical analysis, the late-time behaviour of tilting perfect fluid Bianchi models of types IV and VII$_h$ are investigated. In particular, vacuum plane-wave spacetimes are studied and the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sigbjorn Hervik , Robert van den Hoogen , Alan Coley

We present a new model of the microwave sky in polarization that can be used to simulate data from CMB polarization experiments. We exploit the most recent results from the Planck satellite to provide an accurate description of the diffuse…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Carlos Hervías-Caimapo , Anna Bonaldi , Michael L. Brown

The inflationary paradigm is extremely successful regarding predictions of temperature anisotropies in the CMB. However, inflation also makes predictions for a CMB B-mode polarization, which has not been detected. Moreover, the standard…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Gabriel León , Abhishek Majhi , Elias Okon , Daniel Sudarsky

The primordial anisotropies of the cosmic microwave background (CMB) are linearly polarized via Compton-scattering. The Faraday conversion process during the propagation of polarized CMB photons through regions of the large-scale structure…

Astrophysics · Physics 2010-04-05 Asantha Cooray , Alessandro Melchiorri , Joseph Silk

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…

We point out that polarization measurements as planned for the upcoming PLANCK mission can significantly enhance the accuracy of cosmic parameter estimation compared to the temperature anisotropy spectrum alone. In order to illustrate this,…

Astrophysics · Physics 2007-05-23 Pavel Naselsky , Jens Schmalzing , Jesper Sommer-Larsen , Steen Hannested

Recently a Born-Infeld action for dark energy and dark matter that uses additional affine connections was proposed. At background level, it was shown that the new proposal can mimic the standard cosmological evolution. In Bianchi…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Davi C. Rodrigues

We present a new approach in modelling the polarized Galactic synchrotron emission in the microwave range (20-100 GHz), where this radiation is expected to play the leading role in contaminating the Cosmic Microwave Background (CMB) data.…

Astrophysics · Physics 2009-11-07 G. Bernardi , E. Carretti , R. Fabbri , C. Sbarra , S. Poppi , S. Cortiglioni

Recent cosmological tests have discovered a fresh new set of anomalies in the large-scale isotropy of the universe. Motivated thus by the numerous pieces of evidence for large-scale cosmic isotropy violation with the advent of the…

General Relativity and Quantum Cosmology · Physics 2026-05-20 Tanay Gupta , Sukanta Panda , Rajib Saha

According to standard cosmology, the universe is homogeneous and isotropic at large scales. However, some anisotropies can be observed at the local scale in the universe through various ways. Here we have studied the Bianchi type I model…

General Relativity and Quantum Cosmology · Physics 2022-09-12 Pranjal Sarmah , Umananda Dev Goswami

We present an efficient method to compute CMB anisotropies in non-flat universes. First we derive the Boltzmann equation for cosmic microwave background temperature and polarization fluctuations produced by scalar perturbations in a general…

Astrophysics · Physics 2009-06-16 Matias Zaldarriaga , Uros Seljak , Edmund Bertschinger

Wide area cosmological surveys enable investigation of whether dark energy properties are the same in different directions on the sky. Cosmic microwave background observations strongly restrict any dynamical effects from anisotropy, in an…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-05 Stephen A. Appleby , Eric V. Linder

Bipolar spherical harmonics (BiPoSHs) provide a general formalism for quantifying departures in the cosmic microwave background (CMB) from statistical isotropy (SI) and from Gaussianity. However, prior work has focused only on BiPoSHs with…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Laura G. Book , Marc Kamionkowski , Tarun Souradeep
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