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We have developed a fast method for predicting the angular power spectrum, C_l, of the cosmic microwave background given cosmological parameters and a primordial power spectrum of perturbations. After pre--computing the radiation…

Astrophysics · Physics 2009-11-07 Manoj Kaplinghat , Lloyd Knox , Constantinos Skordis

The concordance of the $\Lambda$CDM cosmological model in light of current observations has been the subject of an intense debate in recent months. The 2018 Planck Cosmic Microwave Background (CMB) temperature anisotropy power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-02 Sunny Vagnozzi , Eleonora Di Valentino , Stefano Gariazzo , Alessandro Melchiorri , Olga Mena , Joseph Silk

We review the constraints given by the linear matter power spectra data on cosmological and bias parameters, comparing the data from the PSCz survey (Hamilton et al., 2000) and from the matter power spectrum infered by the study of Lyman…

Astrophysics · Physics 2009-11-07 M. Douspis , A. Blanchard , J. Silk

Weak lensing of the CMB changes the unlensed temperature anisotropy and polarization power spectra. Accounting for the lensing effect will be crucial to obtain accurate parameter constraints from sensitive CMB observations. Methods for…

Astrophysics · Physics 2009-11-10 Anthony Challinor , Antony Lewis

We extend the resummation method of Anselmi & Pietroni (2012) to compute the total density power spectrum in models of quintessence characterized by a vanishing speed of sound. For standard $\Lambda$CDM cosmologies, this resummation scheme…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Stefano Anselmi , Diana López Nacir , Emiliano Sefusatti

The usual inflationary scenario predicts a Gaussian random primordial density fluctuation, different Fourier modes of which do not correlate with each other. In this paper we propose a correlation between these different modes. A simple…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-12 B. Yu , T. Lu

The primordial curvature fluctuation spectrum is reconstructed by the cosmic inversion method using the five-year WMAP data of the cosmic microwave background temperature anisotropy. We apply the covariance matrix analysis and decompose the…

Astrophysics · Physics 2008-12-30 Ryo Nagata , Jun'ichi Yokoyama

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

In this paper, we study how to directly measure the effect of peculiar velocities in the observed angular power spectra. We do this by constructing a new anti-symmetric estimator of Large Scale Structure using different dark matter tracers.…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-03 José Fonseca , Chris Clarkson

Beyond the linear regime of structure formation, part of cosmological information encoded in galaxy clustering becomes inaccessible to the usual power spectrum. "Sufficient statistics", A*, were introduced recently to recapture the lost,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 M. Wolk , J. Carron , I. Szapudi

We calculate the power spectrum of vacuum fluctuations of a generic scalar field in a quantum cosmological setting that is manifestly singularity-free. The power spectrum is given in terms of the usual scale invariant spectrum plus scale…

Astrophysics · Physics 2007-05-23 S. Hofmann , O. Winkler

With the advent of a new generation of cosmological experiments that will provide high-precision measurements of the cosmic microwave background (CMB) and galaxies in the large-scale structure, it is pertinent to examine the potential of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-27 Shu-Fan Chen , Hayden Lee , Cora Dvorkin

We reexamine the evidence of the hemispherical power asymmetry, detected in the CMB WMAP data using a new method. At first, we analyze the hemispherical variance ratios and compare these with simulated distributions. Secondly, working…

Astrophysics · Physics 2014-11-18 Bartosz Lew

We consider the possibility that the primordial curvature perturbation is direction-dependent. To first order this is parameterised by a quadrupolar modulation of the power spectrum and results in statistical anisotropy of the CMB, which…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-15 Amel Durakovic , Paul Hunt , Suvodip Mukherjee , Subir Sarkar , Tarun Souradeep

In the era of precision cosmology, establishing the correct magnitude of statistical errors in cosmological parameters is of crucial importance. However, widely used approximations in galaxy surveys analyses can lead to parameter…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 Nicola Bellomo , José Luis Bernal , Giulio Scelfo , Alvise Raccanelli , Licia Verde

We use analytic covariance matrices to carry out a full-shape analysis of the galaxy power spectrum multipoles from the Baryon Oscillation Spectroscopic Survey (BOSS). We obtain parameter estimates that agree well with those based on the…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-29 Digvijay Wadekar , Mikhail M. Ivanov , Roman Scoccimarro

The angular power spectrum is a gauge-independent observable that is in principle the natural tool for analysing galaxy number counts. In practice, the problem is that the computational requirements for next-generation spectroscopic surveys…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-12 Stefano Camera , José Fonseca , Roy Maartens , Mário G. Santos

We describe a novel end-to-end approach using Machine Learning to reconstruct the power spectrum of cosmological density perturbations at high redshift from observed quasar spectra. State-of-the-art cosmological simulations of structure…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-21 Maria Han Veiga , Xi Meng , Oleg Y. Gnedin , Nickolay Y. Gnedin , Xun Huan

It is demonstrated that estimators of the angular power spectrum commonly used for the stochastic gravitational-wave background (SGWB) lack a closed-form analytical expression for the likelihood function and, typically, cannot be accurately…

Instrumentation and Methods for Astrophysics · Physics 2026-01-30 Xiangyu Zhang , Erik Floden , Hongru Zhao , Sara Algeri , Galin Jones , Vuk Mandic , Jesse Miller
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