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Inflation gives rise to a nearly scale-invariant spectrum of tensor perturbations (gravitational waves), their contribution to the Cosmic Background Radiation (CBR) anisotropy depends upon the present cosmological parameters as well as…

Astrophysics · Physics 2014-10-13 Michael S. Turner , Yun Wang

The scalar mode polarization of the cosmic microwave background is derived in a spatially closed universe from the Boltzmann equation using the line of sight integral method. The EE and TE multipole coefficients have been extracted…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-10 Pedram Niazy , Amir H. Abbassi

General asymptotic formulas are given for the coefficient $C_\ell$ of the term of multipole number $\ell$ in the temperature correlation function of the cosmic microwave background, in terms of scalar and dipole form factors introduced in a…

Astrophysics · Physics 2009-11-06 Steven Weinberg

We demonstrate that for a cosmic variance limited experiment, CMB E polarization alone places stronger constraints on cosmological parameters than CMB temperature. For example, we show that EE can constrain parameters better than TT by up…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Silvia Galli , Karim Benabed , François Bouchet , Jean-François Cardoso , Franz Elsner , Eric Hivon , Anna Mangilli , Simon Prunet , Benjamin Wandelt

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

We discuss methods for estimating EB and TB spectra of the Cosmic Microwave Background anisotropy maps covering limited sky area. Such odd-parity correlations are expected to vanish whenever parity is not broken. As this is indeed the case…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-18 Julien Grain , Matthieu Tristram , Radek Stompor

It is shown that the fluctuation in the temperature of the cosmic microwave background in any direction may be evaluated as an integral involving scalar and dipole form factors, which incorporate all relevant information about acoustic…

Astrophysics · Physics 2009-11-06 Steven Weinberg

Tensions in cosmological parameters measurement motivate a revisit of the effects of instrumental systematics. In this article, we focus on the Pearson's correlation coefficient of the cosmic microwave background temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-28 Adrien La Posta , Thibaut Louis , Xavier Garrido , Matthieu Tristram , Sophie Henrot-Versillé

This paper presents a completely analytic treatment of cosmological fluctuations whose wavelength is small enough to come within the horizon well before the energy densities of matter and radiation become equal. This analysis yields a…

Astrophysics · Physics 2009-11-07 Steven Weinberg

Consistency checks of cosmological data sets are an important tool because they may suggest systematic errors or the type of modifications to $\Lambda$CDM necessary to resolve current tensions. In this work, we derive an analytic method for…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-22 Joshua A. Kable , Graeme E. Addison , Charles L. Bennett

The recently re-discovered multipole vector approach to understanding the harmonic decomposition of the cosmic microwave background traces its roots to Maxwell's Treatise on Electricity and Magnetism. Taking Maxwell's directional derivative…

Astrophysics · Physics 2007-05-23 Jeffrey R. Weeks

We propose a dipole modulation model for the Cosmic Microwave Background Radiation (CMBR) polarization field. We show that the model leads to correlations between l and l+1 multipoles, exactly as in the case of temperature. We obtain…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-31 Shamik Ghosh , Rahul Kothari , Pankaj Jain , Pranati K. Rath

The important studies of Peebles, and Bond and Efstathiou have led to the formula C_l = const/[l(l +1)] aimed at describing the lower order multipoles of the CMBR temperature variations caused by density perturbations with the flat…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Dimitropoulos , L. P. Grishchuk

We investigate simulation-based bandpower covariance matrices commonly used in cosmological parameter inferences such as the estimation of the tensor-to-scalar ratio $r$. We find that upper limits on $r$ can be biased low by tens of…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-06 Dominic Beck , Ari Cukierman , W. L. Kimmy Wu

We explore the low-l likelihood of the angular spectrum C(l) of masked CMB temperature maps using an adaptive importance sampler. We find that, in spite of a partial sky coverage, the likelihood distribution of each C(l) closely follows an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 K. Benabed , J. -F. Cardoso , S. Prunet , E. Hivon

We propose a novel representation of cosmic microwave anisotropy maps, where each multipole order l is represented by l unit vectors pointing in directions on the sky and an overall magnitude. These "multipole vectors and scalars" transform…

Astrophysics · Physics 2008-11-26 C. J. Copi , D. Huterer , G. D. Starkman

Future cosmic microwave background polarization experiments will search for evidence of primordial tensor modes at large angular scales, in the multipole range $4 \leq \ell \leq 50.$ Because in that range there is some mild evidence of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-26 Gonzalo A. Palma , Bastian Pradenas , Walter Riquelme , Spyros Sypsas

Empirical estimates of the band power covariance matrix are commonly used in cosmic microwave background (CMB) power spectrum analyses. While this approach easily captures correlations in the data, noise in the resulting covariance estimate…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 L. Balkenhol , C. L. Reichardt

The contribution of gravitational wave (tensor metric) and energy density (scalar metric) fluctuations to the cosmic microwave background polarization is computed by numerically solving the relativistic radiation transfer equations. We find…

Astrophysics · Physics 2009-10-22 Robert Crittenden , Richard L. Davis , Paul J. Steinhardt

The cosmic microwave anisotropies in a scenario of large scale structure formation with cold dark matter and texture are discussed and compared with recent observational results of the COBE satellite. A couple of important statistical…

Astrophysics · Physics 2008-11-26 R. Durrer , A. Howard , Z. -H. Zhou
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