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We study statistical anisotropies generated in the observed two-point function of the cosmic microwave background (CMB) fluctuations if the primordial statistics are non-Gaussian. Focusing on the dipole modulations of the anisotropies, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-17 Saroj Adhikari , Anne-Sylvie Deutsch , Sarah Shandera

In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…

Astrophysics · Physics 2009-09-29 Roberto Trotta

The curl-modes of Cosmic Microwave Background (CMB) polarization probe horizon-scale primordial gravitational waves related to inflation. A significant source of confusion is expected from a lensing conversion of polarization related to…

Astrophysics · Physics 2009-11-10 Asantha Cooray

Searches for primordial gravitational waves have resulted in constraints in a large frequency range from a variety of sources. The standard Cosmic Microwave Background (CMB) technique is to parameterise the tensor power spectrum in terms of…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Thomas J. Clarke , Edmund J. Copeland , Adam Moss

We perform a wavelet analysis of the temperature and polarization maps of the Cosmic Microwave Background (CMB) delivered by the WMAP experiment in search for a parity violating signal. Such a signal could be seeded by new physics beyond…

Astrophysics · Physics 2008-11-26 Paolo Cabella , Paolo Natoli , Joseph Silk

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

One of the most intriguing hints of a departure from the standard cosmological model is a large-scale dipolar power asymmetry in the cosmic microwave background (CMB). If not a statistical fluke, its origins must lie in the modulation of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 J. P. Zibin , D. Contreras

The energy spectrum of the cosmic microwave background (CMB) allows constraining episodes of energy release in the early Universe. In this paper we revisit and refine the computations of the cosmological thermalization problem. For this…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 J. Chluba , R. A. Sunyaev

Some theoretical models for the early Universe predict a spike-type enhancement in the primordial power spectrum on a small scale, which would result in forming early-formed dark matter halos~(EFHs). Some recent studies have claimed to have…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-21 Katsuya T. Abe , Hiroyuki Tashiro

We forecast the constraints on both Hu-Sawicki model and Bertschinger-Zukin model of modified gravity within the Parameterized Post-Friedmann (PPF) formalism for the Planck satellite experiment by performing the joint analysis of…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Bin Hu , Michele Liguori , Nicola Bartolo , Sabino Matarrese

If the primordial fluctuations are non-Gaussian, then this non-Gaussianity will be apparent in the cosmic microwave background (CMB) sky. With their sensitive all-sky observation, MAP and Planck satellites should be able to detect weak…

Astrophysics · Physics 2009-07-09 Eiichiro Komatsu , David N. Spergel

Upcoming cosmic microwave background (CMB) surveys will soon make the first detection of the polarized Sunyaev-Zel'dovich effect, the linear polarization generated by the scattering of CMB photons on the free electrons present in collapsed…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-04 Joel Meyers , P. Daniel Meerburg , Alexander van Engelen , Nicholas Battaglia

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…

Recent satellite observations have revealed significant anisotropy in the cosmic microwave background (CMB) radiation, a phenomenon that had previously been detected but received limited attention due to its subtlety. With the advent of…

General Relativity and Quantum Cosmology · Physics 2025-02-10 S. Davood Sadatian , Amir Sabouri , Zahra Davari

We discuss the polarization signature of primordial gravitational waves imprinted in cosmic microwave background (CMB) anisotropies. The high-energy physics motivated by superstring theory or M-theory generically yield parity violating…

Astrophysics · Physics 2009-06-23 Shun Saito , Kiyotomo Ichiki , Atsushi Taruya

In this paper we study the possibility of testing Charge-Parity-Time Reversal (CPT) symmetry with cosmic microwave background (CMB) experiments. We consider two kinds of Chern-Simons (CS) term, electromagnetic CS term and gravitational CS…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Jun-Qing Xia

We study the physical limitations placed on CMB temperature and polarization measurements of the initial power spectrum by geometric projection, acoustic physics, gravitational lensing and the joint fitting of cosmological parameters.…

Astrophysics · Physics 2009-11-10 Wayne Hu , Takemi Okamoto

Perturbations from inflation evolve into large scale structure of the late universe, and encode abundant cosmic structure formation physics. We allow freedom in the primordial power spectrum, rather than assuming a power law scale…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-12 Guilherme Brando , Eric V. Linder

We present updated constraints on the variation of the fine structure constant, $\alpha_{\rm EM}$, and effective electron rest mass, $m_{\rm e}$, during the cosmological recombination era. These two fundamental constants directly affect the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-25 Luke Hart , Jens Chluba

The cosmic microwave background (CMB) temperature autocorrelations, induced by a magnetized adiabatic mode of curvature inhomogeneities, are computed with semi-analytical methods. As suggested by the latest CMB data, a nearly…

Astrophysics · Physics 2008-11-26 Massimo Giovannini
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