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Related papers: A Proposal for Constraining Initial Vacuum by CMB

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We describe an efficient and exact method that enables global Bayesian analysis of cosmic microwave background (CMB) data. The method reveals the joint posterior density (or likelihood for flat priors) of the power spectrum $C_\ell$ and the…

Astrophysics · Physics 2009-11-10 Benjamin D. Wandelt , David L. Larson , Arun Lakshminarayanan

Using the covariant formalism developed in a companion paper (paper I), we derive observational constraint on the Brans-Dicke model in a flat FLRW universe with cosmological constant and cold dark matter. The CMB observations we use include…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Fengquan Wu , Xuelei Chen

We investigate the ability to constrain oscillatory features in the primordial power spectrum using current and future cosmic microwave background observations. In particular, we study the observability of an oscillation arising from…

Astrophysics · Physics 2011-05-12 Takemi Okamoto , Eugene A. Lim

It is well known that estimating cosmological parameters from cosmic microwave background (CMB) data alone results in a significant degeneracy between the total neutrino mass and several other cosmological parameters, especially the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-28 Will Sutherland

I present a pedagogical review of inflation and the cosmic microwave background. I describe how a short period of accelerated expansion can replace the special initial conditions of the standard big bang model. I also describe the…

Astrophysics · Physics 2017-08-23 Charles H. Lineweaver

Anisotropies of the cosmic microwave background (CMB) have proven to be a very powerful tool to constrain dark matter annihilation at the epoch of recombination. However, CMB constraints are currently derived using a number of reasonable…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Silvia Galli , Tracy R. Slatyer , Marcos Valdes , Fabio Iocco

Departures of the energy spectrum of the cosmic microwave background (CMB) from a perfect blackbody probe a fundamental property of the universe -- its thermal history. Current upper limits, dating back some 25 years, limit such spectral…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-01 A. Kogut , M. H. Abitbol , J. Chluba , J. Delabrouille , D. Fixsen , J. C. Hill , S. P. Patil , A. Rotti

We devise a measure n(r) to quantify a robust feature in the coherent cosmic perturbations, namely the narrowness of the first peak in the power spectrum of the Cosmic Microwave Background (CMB) anisotropy. A maximum-likelihood analysis…

Astrophysics · Physics 2007-05-23 Jiun-Huei Proty Wu

We investigate the dependence of cosmological parameters on the number count of peaks (local maxima and minima) in the cosmic microwave background (CMB) sky. The peak statistics contains the whole information of acoustic oscillations in the…

Astrophysics · Physics 2007-05-23 Toshifumi Futamase , Masahiro Takada

In addition to its spectrum and temperature anisotropy, the 2.7K Cosmic Microwave Background is also expected to exhibit a low level of polarization. The spatial power spectrum of the polarization can provide details about the formation of…

Astrophysics · Physics 2009-10-30 Brian Keating , Peter Timbie , Alexander Polnarev , Julia Steinberger

Gaussianity of the cosmological perturbations in the universe is one of the key predictions of standard inflation, but it is violated by other models of structure formation such as topological defects. We present the first test of the…

We present calculations showing that upcoming Cosmic Microwave Background (CMB) experiments will have the power to improve on current constraints on neutrino masses and provide new limits on neutrino degeneracy parameters. The latter could…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Shimon , N. J. Miller , C. T. Kishimoto , C. J. Smith , G. M. Fuller , B. G. Keating

The cosmic microwave background (CMB) and baryon acoustic oscillations (BAO) provide precise measurements of the cosmic expansion history through the comoving acoustic scale. The CMB angular scale measurement $\theta_*$ is particularly…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-24 Antony Lewis , Ewan Chamberlain

B-modes of Cosmic Microwave Background (CMB) polarization can be created by a primordial gravitational wave background. If this background was created by Inflation, then the amplitude of the polarization signal is proportional the energy…

Astrophysics · Physics 2008-11-26 Alexandre Amblard , Asantha Cooray , Manoj Kaplinghat

We have investigated the cosmic microwave background (CMB) anisotropy in closed multiply connected universes (flat and hyperbolic) with low matter density. We show that the COBE constraints on these low matter density models with…

Astrophysics · Physics 2016-08-30 Kaiki Taro Inoue

We calculate the cosmic microwave background (CMB) bispectrum due to inhomogeneous reionization. We calculate all the terms that can contribute to the bispectrum that are products of first order terms on all scales in conformal Newtonian…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Rishi Khatri , Benjamin D. Wandelt

Details of how the primordial plasma recombined and how the universe later reionized are currently somewhat uncertain. This uncertainty can restrict the accuracy of cosmological parameter measurements from the Cosmic Microwave Background…

Astrophysics · Physics 2008-11-26 Antony Lewis , Jochen Weller , Richard Battye

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

We present a method for calculating large numbers of power spectra C_l and P(k) that accelerates CMBfast by a factor around 10^3 without appreciable loss of accuracy, then apply it to constrain 11 cosmological parameters from current Cosmic…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga , Andrew J. S. Hamilton
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