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In this paper, we present the first study that compares different models of Bayesian Neural Networks (BNNs) to predict the posterior distribution of the cosmological parameters directly from the Cosmic Microwave Background temperature and…

Instrumentation and Methods for Astrophysics · Physics 2020-11-13 Hector J. Hortua , Riccardo Volpi , Dimitri Marinelli , Luigi Malagò

Cosmic Microwave Background experiments must achieve very accurate calibration of their polarization reference frame to avoid biasing the cosmological parameters. In particular, a wrong or inaccurate calibration might mimic the presence of…

We investigate signatures of neutrino scattering in the Cosmic Microwave Background (CMB) and matter power spectra, and the extent to which present cosmological data can distinguish between a free streaming or tightly coupled fluid of…

Astrophysics · Physics 2007-05-23 Nicole F. Bell , Elena Pierpaoli , Kris Sigurdson

When fitting cosmological models to data, a Bayesian framework is commonly used, requiring assumptions on the form of the likelihood and model prior. In light of current tensions between different data, it is interesting to investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Jordan Krywonos , Simone Paradiso , Alex Krolewski , Shahab Joudaki , Will Percival

The polarization of the cosmic microwave background (CMB) can be used to search for parity-violating processes like that predicted by a Chern-Simons coupling to a light pseudoscalar field. Such an interaction rotates $E$ modes into $B$…

We discuss the cosmological degeneracy between the age of the Universe, the Hubble parameter and the effective number of relativistic particles N_eff. We show that independent determinations of the Hubble parameter H(z) as those recently…

Astrophysics · Physics 2008-11-26 Francesco de Bernardis , Alessandro Melchiorri , Licia Verde , Raul Jimenez

The polarization of cosmic microwave background (CMB) can be used to constrain cosmological birefringence, the rotation of the linear polarization of CMB photons potentially induced by parity violating physics beyond the standard model.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 A. Gruppuso , M. Gerbino , P. Natoli , L. Pagano , N. Mandolesi , D. Molinari

The search for primordial gravitational waves in the Cosmic Microwave Background (CMB) will soon be limited by our ability to remove the lensing contamination to $B$-mode polarization. The often-used quadratic estimator for lensing is known…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Marius Millea , Ethan Anderes , Benjamin D. Wandelt

We examine the degree to which observations of large-scale cosmic microwave background (CMB) polarization can shed light on the puzzling large-scale power modulation in maps of CMB anisotropy. We consider a phenomenological model in which…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Emory F. Bunn , Qingyang Xue , Haoxuan Zheng

Accurate parameter estimation from cosmic microwave background data requires reliable likelihood modeling, particularly at large angular scales where angular power spectrum estimators exhibit non-Gaussian statistics. We present a novel…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-23 Giacomo Galloni , Paolo Campeti , Luca Pagano , Martina Gerbino , Massimiliano Lattanzi , Paolo Natoli

Observational astrophysics consists of making inferences about the Universe by comparing data and models. The credible intervals placed on model parameters are often as important as the maximum a posteriori probability values, as the…

Instrumentation and Methods for Astrophysics · Physics 2021-12-15 Will J. Percival , Oliver Friedrich , Elena Sellentin , Alan Heavens

The vast majority of extensions of the Standard Model affecting the number of effective relativistic neutrino species ($N_{\rm eff}$) do so additively, namely, they enhance this quantity with some light state contributing to dark radiation.…

High Energy Physics - Phenomenology · Physics 2026-04-03 Miguel Escudero , Maksym Ovchynnikov , Neal Weiner

Recent indications from both particle physics and cosmology suggest the existence of more than three neutrino species. In cosmological analyses the effects of neutrino mass and number of species can in principle be disentangled for fixed…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Signe Riemer-Sorensen , David Parkinson , Tamara Davis , Chris Blake

A method is presented for performing joint analyses of cosmological datasets, in which the weight assigned to each dataset is determined directly by it own statistical properties. The weights are considered in a Bayesian context as a set of…

Astrophysics · Physics 2009-11-07 M. P. Hobson , S. L. Bridle , O. Lahav

Bayesian model selection provides a formal method of determining the level of support for new parameters in a model. However, if there is not a specific enough underlying physical motivation for the new parameters it can be hard to assign…

Astrophysics · Physics 2009-11-13 Christopher Gordon , Roberto Trotta

We present the results of analysis of constraints on cosmological parameters from cosmic microwave background (CMB) alone and in combination with galaxy cluster baryon fraction assuming inflation--generated adiabatic scalar fluctuations.…

Astrophysics · Physics 2009-11-06 M. Douspis , A. Blanchard , R. Sadat , J. G. Bartlett , M. Le Dour

In universes with significant curvature or cosmological constant, cosmic microwave background (CMB) anisotropies are created very recently via the Rees-Sciama or integrated Sachs-Wolfe effects. This causes the CMB anisotropies to become…

Astrophysics · Physics 2009-10-30 S. P. Boughn , R. G. Crittenden , N. G. Turok

We describe the subject of Cosmic Microwave Background (CMB) analysis - its past, present and future. The theory of Gaussian primary anisotropies, those arising from linear physics operating in the early Universe, is in reasonably good…

Astrophysics · Physics 2010-05-12 J. Richard Bond , Robert G. Crittenden

Observations of the Cosmic Microwave Background (CMB) are discussed, with particular emphasis on current ground-based experiments and on future satellite, balloon and interferometer experiments. Observational techniques and the effects of…

Astrophysics · Physics 2009-10-31 A. N. Lasenby , A. W. Jones , Y. Dabrowski

The cosmic microwave background (CMB) temperature bispectrum is currently the most precise tool for constraining primordial non-Gaussianity (NG). The Planck temperature data tightly constrain the amplitude of local-type NG: $f_{\rm NL}^{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-06 J. Colin Hill