English
Related papers

Related papers: A brute force analysis of the COBE DMR data

200 papers

We present simulation-based cosmological $w$CDM inference using Dark Energy Survey Year 3 weak-lensing maps, via neural data compression of weak-lensing map summary statistics: power spectra, peak counts, and direct map-level…

Developing accurate analysis techniques to combine various probes of cosmology is essential to tighten constraints on cosmological parameters and to check for inconsistencies in our model of the Universe. In this paper we develop a joint…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Tim Eifler , Elisabeth Krause , Peter Schneider , Klaus Honscheid

This work considers Maximum Likelihood Estimation (MLE) of a Toeplitz structured covariance matrix. In this regard, an equivalent reformulation of the MLE problem is introduced and two iterative algorithms are proposed for the optimization…

Signal Processing · Electrical Eng. & Systems 2025-05-13 Augusto Aubry , Prabhu Babu , Antonio De Maio , Massimo Rosamilia

We extend the analysis of Gabor transforms on a Cosmic Microwave Background (CMB) temperature map (Hansen, Gorski and Hivon 2002) to polarisation. We study the temperature and polarisation power spectra on the cut sky, the so-called pseudo…

Astrophysics · Physics 2008-11-26 Frode K. Hansen , Krzysztof M. Gorski

Likelihood analyses of the COBE-DMR sky maps are used to determine the normalization of the inverse-power-law-potential scalar field dark energy model. Predictions of the DMR-normalized model are compared to various observations to…

We apply the massively optimized parameter estimation and data compression technique (MOPED) to the public Planck 2015 temperature likelihood, reducing the dimensions of the data space to one number per parameter of interest. We present…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Heather Prince , Jo Dunkley

The two-year COBE-DMR 53 and 90 GHz sky maps are used to determine the normalization of inflationary, cosmological constant dominated, cold dark matter models. Although the COBE-DMR data prefer a nearly critical value for the total density,…

Astrophysics · Physics 2009-09-25 Radoslaw Stompor , Krzysztof M. Gorski , Anthony J. Banday

The power spectrum (PS) of {\it mass} density fluctuations, independent of ``biasing", is estimated from the Mark3 Catalog of Peculiar Velocities of galaxies using Bayesian statistics. A parametric model is assumed for the PS, and the free…

Astrophysics · Physics 2016-08-30 S. Zaroubi , A. Dekel , Y. Hoffman , T. Kolatt

This paper studies the qualitative behavior and robustness of two variants of Minimal Random Code Learning (MIRACLE) used to compress variational Bayesian neural networks. MIRACLE implements a powerful, conditionally Gaussian variational…

Machine Learning · Computer Science 2023-12-05 Jihao Andreas Lin , Gergely Flamich , José Miguel Hernández-Lobato

Context. Gravitational lensing is one of the leading tools in understanding the dark side of the Universe. The need for accurate, efficient and effective methods which are able to extract this information along with other cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Marika Asgari , Peter Schneider , Patrick Simon

The smaller the angular scales on which the anisotropies of the cosmic microwave background (CMB) are probed the more important their distortion due to gravitational lensing becomes. Here we investigate the maxima and minima of the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Philipp M. Merkel , Bjoern Malte Schaefer

We develop extreme data compression for use in Bayesian model comparison via the MOPED algorithm, as well as more general score compression. We find that Bayes factors from data compressed with the MOPED algorithm are identical to those…

Instrumentation and Methods for Astrophysics · Physics 2023-07-17 Alan F. Heavens , Arrykrishna Mootoovaloo , Roberto Trotta , Elena Sellentin

Recent cosmic microwave background (CMB) measurements over a large range of angular scales have become sensitive enough to provide interesting constraints on cosmological parameters within a restricted class of models. We use the CMB…

Astrophysics · Physics 2008-02-03 Charles H. Lineweaver , Domingos Barbosa

We discuss the problem of CMB spectrum corruption during Galactic emission removing. A new technique of spatial--frequency data reduction is proposed. The technique gives us a possibility to avoid a spatial harmonics nonorthogonality. The…

Astrophysics · Physics 2007-05-23 A. A. Brukhanov , D. P. Skulachev , I. A. Strukov , T. V. Konkina

The COnstrain Dark Energy with X-ray clusters (CODEX) sample contains the largest flux limited sample of X-ray clusters at $0.35 < z < 0.65$. It was selected from ROSAT data in the 10,000 square degrees of overlap with BOSS, mapping a total…

We consider the problem of estimating the inverse covariance matrix by maximizing the likelihood function with a penalty added to encourage the sparsity of the resulting matrix. We propose a new approach based on the split Bregman method to…

Machine Learning · Statistics 2015-03-17 Gui-Bo Ye , Jian-Feng Cai , Xiaohui Xie

We propose a formalism for estimating the skewness and angular power spectrum of a general Cosmic Microwave Background data set. We use the Edgeworth Expansion to define a non-Gaussian likelihood function that takes into account the…

Astrophysics · Physics 2010-04-30 C. R. Contaldi , P. G. Ferreira , J. Magueijo , K. M. Gorski

We investigate the Gaussianity of the 4-year COBE-DMR data (in HEALPix pixelisation) using an analysis based on spherical Haar wavelets. We use all the pixels lying outside the Galactic cut and compute the skewness, kurtosis and scale-scale…

Astrophysics · Physics 2015-06-24 R. B. Barreiro , M. P. Hobson , A. N. Lasenby , A. J. Banday , K. M. Gorski , G. Hinshaw

We formulate the problem of performing optimal data compression under the constraints that compressed data can be used for accurate classification in machine learning. We show that this translates to a problem of minimizing the mutual…

Signal Processing · Electrical Eng. & Systems 2022-11-04 Jingchao Gao , Ao Tang , Weiyu Xu

Accurate covariance matrices are required for a reliable estimation of cosmological parameters from pseudo-power spectrum estimators. In this work, we focus on the analytical calculation of covariance matrices. We consider the case of…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-08 Étienne Camphuis , Karim Benabed , Silvia Galli , Éric Hivon , Marc Lilley