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Related papers: Density Perturbations,Gravity Waves and the Cosmic…

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I give a status report and outlook concerning the use of the cosmic microwave background anisotropies to constrain the inflationary cosmology, and stress its crucial role as an underlying paradigm for the estimation of cosmological…

Astrophysics · Physics 2009-10-30 Andrew R Liddle

The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first…

Inflationary models predict a correlation between primordial density perturbations (scalar metric perturbations) and gravitational waves (tensor metric perturbations) in the form of a scalar-scalar-tensor three-point correlation, or…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Liang Dai , Donghui Jeong , Marc Kamionkowski

Recently, BICEP2 measurements of the cosmic microwave background (CMB) $B$-mode polarization at degree angular scales has indicated the presence of tensor modes with a high tensor-to-scalar ratio of $r=0.2$ when assuming nearly…

High Energy Physics - Phenomenology · Physics 2015-06-22 Guo-Chin Liu , Kin-Wang Ng , I-Chin Wang

It is commonly assumed that the stochastic background of gravitational waves on cosmological scales follows an almost scale-independent power spectrum, as generically predicted by the inflationary paradigm. However, it is not inconceivable…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Jan Hamann , Ameek Malhotra

We examine stochastic temperature fluctuations of the cosmic background radiation (CBR) arising via the Sachs-Wolfe effect from gravitational wave perturbations produced in the early universe. We consider spatially flat, perturbed FRW…

Astrophysics · Physics 2009-10-22 Scott Koranda , Bruce Allen

We evaluate the modifications to the cosmic microwave background anisotropy spectrum that result from a semiclassical expansion of the Wheeler-DeWitt equation. Recently, such an investigation in the case of a real scalar field coupled to…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Donato Bini , Giampiero Esposito , Claus Kiefer , Manuel Kraemer , Francesco Pessina

We investigate large-angle scale temperature anisotropy in the Cosmic Microwave Background (CMB) with the Wilkinson Microwave Anisotropy Probe (WMAP) data and model the large-angle anomalies as the effect of the CMB quadrupole anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Li-Ping He , Quan Guo

The Cosmological Gravitational Wave Background (CGWB) anisotropies contain valuable information about the physics of the early universe. Given that General Relativity is intrinsically nonlinear, it is important to look beyond first-order…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-29 Alina Mierna , Sabino Matarrese , Nicola Bartolo , Angelo Ricciardone

The analysis of anisotropies in the cosmic microwave background (CMB) has become an extremely valuable tool for cosmology. We even have hopes that planned CMB anisotropy experiments may revolutionize cosmology. Together with determinations…

Astrophysics · Physics 2011-04-15 Ruth Durrer

Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years.…

Astrophysics · Physics 2007-05-23 Scott Dodelson

While large scale cosmic microwave background (CMB) anisotropies involve a combination of the scalar and tensor fluctuations, the scalar amplitude can be independently determined through the CMB-galaxy cross-correlation. Using recently…

Astrophysics · Physics 2008-11-26 A. Cooray , P. S. Corasaniti , T. Giannantonio , A. Melchiorri

We combine detections of anisotropy in the Cosmic Microwave Background radiation with observations of inhomogeneity in the large-scale distribution of galaxies to test the predictions of models of cosmological structure formation. This…

Astrophysics · Physics 2009-09-25 Eric Gawiser

In this work we study the imprints of a primordial cosmic string on inflationary power spectrum. Cosmic string induces two distinct contributions on curvature perturbations power spectrum. The first type of correction respects the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Sadra Jazayeri , Alireza Vafaei Sadr , Hassan Firouzjahi

We show that the difference between the theoretically expected and measured by WMAP amplitude of the quadrupole fluctuations of CMB can be related to the impact of the anisotropic curvature of the homogeneous universe dominated by the dark…

Astrophysics · Physics 2008-11-26 M. Demiański , A. G. Doroshkevich

We point out three correlated predictions of the axion monodromy inflation model: large amplitude of gravitational waves, suppression of power on horizon scales and on scales relevant for the formation of dwarf galaxies. While these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Quinn E. Minor , Manoj Kaplinghat

A brief account is given of large-scale structure modelling based on the assumption that the initial perturbations arise from inflation. A recap is made of the implications of inflation for large-scale structure; under the widely applicable…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

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

The bispectrum of primordial curvature perturbations in the squeezed configuration, in which one wavenumber, $k_3$, is much smaller than the other two, $k_3\ll k_1\approx k_2$, plays a special role in constraining the physics of inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-07 Maresuke Shiraishi , Eiichiro Komatsu , Marco Peloso , Neil Barnaby

Cosmic microwave background (CMB) anisotropies and density fluctuations are calculated for flat cold dark matter (CDM) models with a wide range of parameters, i.e., $\Omega_0, h$ and $\Omega_B$ for both standard recombination and various…

Astrophysics · Physics 2009-10-22 Naoshi Sugiyama