English
Related papers

Related papers: Cosmic Microwave Background from Late-Decaying Sca…

200 papers

We consider a double-inflationary model with two massive scalar fields interacting only gravitationally in the context of a flat cold dark matter (CDM) Universe. The cosmic microwave background (CMB) temperature anisotropies produced in…

Astrophysics · Physics 2009-10-30 Julien Lesgourgues , David Polarski

Mainly used to set constraints on cosmological parameters, CMB anisotropies can give information on primordial universe. Unfortunately, initial conditions and late time cosmology are degenerated. I focus on the effect of the shape of the…

Astrophysics · Physics 2007-05-23 Marian Douspis

I review the basic theory of the cosmic microwave background anisotropies in adiabatic cold dark matter cosmologies. The latest observational results on the CMB power spectrum are consistent with the simplest inflationary models and…

Astrophysics · Physics 2009-09-25 G. Efstathiou

Recent cosmic microwave background (CMB) observations put strong constraints on the spatial curvature via estimation of the parameter $\Omega_k$ assuming an almost scale invariant primordial power spectrum. We study the evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-31 Béatrice Bonga , Brajesh Gupt , Nelson Yokomizo

The Milky Way can act as a large-scale weak gravitational lens of the cosmic microwave background (CMB). We study this effect using a photon ray-tracing code and a Galactic mass distribution with disk, bulge and halo components. For an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Benjamin Czaja , Benjamin C. Bromley

If the hemispherical power asymmetry observed in the cosmic microwave background (CMB) on large angular scales is attributable to a superhorizon curvaton fluctuation, then the simplest model predicts that the primordial density fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Adrienne L. Erickcek , Christopher M. Hirata , Marc Kamionkowski

The anisotropy and polarization of the cosmic microwave background radiation (CMBR) induced by the scalar and tensor metric perturbations are computed in the long-wavelength limit. It is found that the large-scale polarization of CMBR…

Astrophysics · Physics 2009-10-22 Ka Lok Ng , Kin-Wang Ng

In this paper, inflationary cosmology is reviewed, paying particular attention to its observational signatures associated with large-scale density perturbations generated from quantum fluctuations. In the most general scalar-tensor theories…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-13 Shinji Tsujikawa

Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-13 Stephen M. Feeney , Matthew C. Johnson , Daniel J. Mortlock , Hiranya V. Peiris

I describe briefly the Cosmic Microwave Background (hereafter CMB) physics which explains why high accuracy observations of its spatial structure are a unique observational tool both for the determination of the global cosmological…

Astrophysics · Physics 2007-05-23 Francois R. Bouchet

In this thesis we investigate several aspects related to the theory of fluctuations in the Cosmic Microwave Background. We develop a new algorithm to calculate the angular power spectrum of the anisotropies which is two orders of magnitude…

Astrophysics · Physics 2007-05-23 Matias Zaldarriaga

The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information and high…

The major contribution to the anisotropy of the temperature of the Cosmic Microwave Background (CMB) radiation is believed to come from the interaction of linear density perturbations with the radiation previous to the decoupling time.…

Astrophysics · Physics 2015-06-24 Enrique Martinez-Gonzalez

We predict the imprint of linear bubbly perturbations on the polarization and temperature anisotropies of the cosmic microwave background (CMB). We analytically model a bubbly density perturbation at the beginning of the radiation dominated…

Astrophysics · Physics 2009-10-31 Carlo Baccigalupi , Francesca Perrotta

It is well-known that first order phase transitions in the early universe can be a powerful source of observable stochastic gravitational wave backgrounds. Any such gravitational wave background must exhibit large-scale anisotropies at…

High Energy Physics - Phenomenology · Physics 2023-06-21 Arushi Bodas , Raman Sundrum

We investigate a statistical anisotropy on the Cosmic Microwave Background (CMB) bispectrum, which can be generated from the primordial non-Gaussianity induced by quantum fluctuations of a vector field. We find new configurations in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-03 Maresuke Shiraishi , Shuichiro Yokoyama

Working toward a model independent understanding of cosmic microwave background (CMB) anisotropies and their significance, we undertake a comprehensive and self-contained study of scalar perturbation theory. Initial conditions, evolution,…

Astrophysics · Physics 2009-09-25 Wayne Hu , Naoshi Sugiyama

We calculate the cosmic microwave background (CMB) anisotropy spectrum in models with millicharged particles of electric charge q\sim 10^{-6}-10^{-1} in units of electron charge. We find that a large region of the parameter space for the…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. L. Dubovsky , D. S. Gorbunov , G. I. Rubtsov

We present an alternative scenario for cosmic structure formation where initial fluctuations are due to Kalb-Ramond axions produced during a pre-big bang phase of inflation. We investigate whether this scenario, where the fluctuations are…

Astrophysics · Physics 2009-10-31 Filippo Vernizzi , Alessandro Melchiorri , Ruth Durrer

We consider the hypothesis that nonlocal, omnidirectional, causally-coherent quantum entanglement of inflationary horizons may account for some well-known measured anomalies of Cosmic Microwave Background (CMB) anisotropy on large angular…

General Relativity and Quantum Cosmology · Physics 2022-02-16 Craig Hogan , Stephan S. Meyer