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We review evidence for a new phenomenon in the propagation of radio waves across the Universe, an anisotropic rotation of the plane of polarization not accounted for by conventional physics.

Astrophysics · Physics 2009-10-30 John P. Ralston , Borge Nodland

It is shown that rotational cosmological perturbations can be generated in the early Universe, similarly to gravitational waves. The generating mechanism is quantum-mechanical in its nature, and the created perturbations should now be…

General Relativity and Quantum Cosmology · Physics 2010-11-19 L. P. Grishchuk

In this review, we give an overview of some of the major aspects of data reduction and analysis for the cosmic microwave background (CMB). Since its prediction and discovery in the last century, the CMB radiation has proven itself to be one…

Astrophysics · Physics 2009-09-29 Matthieu Tristram , Ken Ganga

I explain the origin and evolution of anisotropies in the Cosmic Microwave Background (CMB) and argue that upcoming experiments will measure cosmological and fundamental parameters very accurately. Most of the paper focuses on present data,…

High Energy Physics - Phenomenology · Physics 2014-11-17 Scott Dodelson

We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave background observations. The topic is of…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-05 D. Herranz , P. Vielva

A compact overview of the status of CMB anisotropy results and their cosmological interpretation. Section headings: Introduction; CMB Spectrum; Description of CMB Anisotropies; Cosmological Parameters; Physics of Anisotropies; Current…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-09 Douglas Scott , George F. Smoot

This is a course on cosmic microwave background (CMB) anisotropies in the standard cosmological model, designed for beginning graduate students and advanced undergraduates. ``Standard cosmological model'' in this context means a Universe…

Astrophysics · Physics 2009-10-31 James G. Bartlett

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

The information theory approach is suggested to the Cosmic Microwave Background (CMB) problem for negatively curved homogeneous and isotropic Universe. Namely, the Kolmogorov complexity of anisotropy of spots in CMB sky maps is proposed as…

Astrophysics · Physics 2009-10-31 V. G. Gurzadyan

A future detection of the Stochastic Gravitational Wave Background (SGWB) with GW experiments is expected to open a new window on early universe cosmology and on the astrophysics of compact objects. In this paper we study SGWB anisotropies,…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 N. Bartolo , D. Bertacca , S. Matarrese , M. Peloso , A. Ricciardone , A. Riotto , G. Tasinato

There is tentative evidence for a mismatch between the rest frames of matter and the cosmic microwave background, the "quasar dipole anomaly". We consider such a dipole in tilted anisotropic models, for a range of scenarios and sources:…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-04 Alicia Martín , Constantinos Skordis , Deaglan J. Bartlett , Harry Desmond , Pedro G. Ferreira , Tariq Yasin

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

We introduce a general class of models for charaterizing the non-Gaussian properties of foreground contaminants in the cosmic microwave background with view towards the removal of the non-primordial non-Gaussian signal from the primordial…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 C. S. Carvalho

Anisotropies in the cosmic microwave background radiation due to gravity waves are investigated. An initial spectrum of gravity waves may have been induced during an epoch of inflation. We study the propagation of such a spectrum in a…

Astrophysics · Physics 2008-02-03 Ruth Durrer , Tina Kahniashvili

We show the existence of spatially homogeneous but anisotropic cosmological models whose cosmic microwave background temperature is exactly isotropic at one instant of time but whose rate of expansion is highly anisotropic. The existence of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 W C Lim , U S Nilsson , J Wainwright

First the second-order perturbations of nonzero-\Lambda cosmological models are derived with an arbitrary potential function of spatial coordinates, using the nonlinear version of Lifshitz's method in the synchronous gauge. Their expression…

Astrophysics · Physics 2009-11-10 Kenji Tomita

We have independently measured the genus topology of the temperature fluctuations in the cosmic microwave background seen by the Wilkinson Microwave Anisotropy Probe (WMAP). A genus analysis of the WMAP data indicates consistency with…

Astrophysics · Physics 2011-05-10 Wesley N. Colley , J. Richard Gott

We consider anisotropies in the stochastic background of gravitational-waves (SBGW) arising from random fluctuations in the number of gravitational-wave sources. We first develop the general formalism which can be applied to different…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 S. Olmez , V. Mandic , X. Siemens

Identifying the anisotropies in a cosmologically sourced stochastic gravitational wave background (SGWB) would be of significance in shedding light on the nature of primordial inhomogeneities. For example, if SGWB carries isocurvature…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-18 Yanou Cui , Soubhik Kumar , Raman Sundrum , Yuhsin Tsai

A new method for modelling spherically symmetric inhomogeneities is applied to the formation of clusters in an expanding Universe. We impose simple initial velocity and density perturbations of finite extent and we investigate the…

Astrophysics · Physics 2009-10-31 Y. Dabrowski , M. P. Hobson , A. N. Lasenby , C. J. L. Doran
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