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We quantify the information content of the non-linear matter power spectrum, the halo mass function, and the void size function, using the Quijote $N$-body simulations. We find that these three statistics exhibit very different degeneracies…

We present a joint likelihood analysis of the halo power spectrum and bispectrum in real space. We take advantage of a large set of numerical simulations and of an even larger set of halo mock catalogs to provide a robust estimate of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-23 Andrea Oddo , Federico Rizzo , Emiliano Sefusatti , Cristiano Porciani , Pierluigi Monaco

We apply a Machine Learning technique known as Convolutional Denoising Autoencoder to denoise synthetic images of state-of-the-art radio telescopes, with the goal of detecting the faint, diffused radio sources predicted to characterise the…

Instrumentation and Methods for Astrophysics · Physics 2021-11-03 Claudio Gheller , Franco Vazza

Deep neural network models have a complex architecture and are overparameterized. The number of parameters is more than the whole dataset, which is highly resource-consuming. This complicates their application and limits its usage on…

Computer Vision and Pattern Recognition · Computer Science 2024-08-15 Vasiliy Alekseev , Ilya Lukashevich , Ilia Zharikov , Ilya Vasiliev

We present a neural net algorithm for parameter estimation in the context of large cosmological data sets. Cosmological data sets present a particular challenge to pattern-recognition algorithms since the input patterns (galaxy redshift…

Astrophysics · Physics 2007-05-23 Nicholas G. Phillips , A. Kogut

We explore a variety of statistics of clusters selected with cosmic shear measurement by utilizing both analytic models and large numerical simulations. We first develop a halo model to predict the abundance and the clustering of weak…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Masato Shirasaki , Takashi Hamana , Naoki Yoshida

Inferring a process matrix characterizing a quantum channel from experimental measurements is a key issue of quantum information. Sometimes the noise affecting the measured counts brings to matrices very different from the expected ones and…

Quantum Physics · Physics 2024-01-31 Massimiliano Guarneri , Andrea Chiuri

The determination of the covariance matrix and its inverse, the precision matrix, is critical in the statistical analysis of cosmological measurements. The covariance matrix is typically estimated with a limited number of simulations at…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Marnix J. Looijmans , Mike Shengbo Wang , Florian Beutler

Current and forthcoming cosmological data analyses share the challenge of huge datasets alongside increasingly tight requirements on the precision and accuracy of extracted cosmological parameters. The community is becoming increasingly…

Instrumentation and Methods for Astrophysics · Physics 2014-12-17 Benjamin Joachimi , Andy Taylor

Sparsity in the eigenvectors of signal covariance matrices is exploited in this paper for compression and denoising. Dimensionality reduction (DR) and quantization modules present in many practical compression schemes such as transform…

Applications · Statistics 2015-06-03 Ioannis D. Schizas , Georgios B. Giannakis

For many analyses in cosmology it is necessary to reconstruct the likely distribution of unobserved fields, such as dark matter or non-luminous baryons, from observed luminous tracers. The dominant approach in cosmology has been to use the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-16 Jordan Krywonos , Yurii Kvasiuk , Matthew C. Johnson , Moritz Münchmeyer

Cosmological parameter estimation requires that the likelihood function of the data is accurately known. Assuming that cosmological large-scale structure power spectra data are multivariate Gaussian-distributed, we show the accuracy of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Andy Taylor , Benjamin Joachimi , Thomas Kitching

Abstract Covariance matrix estimation is a challenging problem in cosmology. Recent work has shown that model covariance matrices can be precise, and that at relatively large scales they can also be accurate. We introduce a data-driven…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-13 Ross O'Connell

Analysis and denoising of Cosmic Microwave Background (CMB) maps are performed using wavelet multiresolution techniques. The method is tested on $12^{\circ}.8\times 12^{\circ}.8$ maps with resolution resembling the experimental one expected…

Astrophysics · Physics 2009-10-31 J. L. Sanz , F. Argueso , L. Cayon , E. Martinez-Gonzalez , R. B. Barreiro , L. Toffolatti

We present a neural net algorithm for parameter estimation in the context of large cosmological data sets. Cosmological data sets present a particular challenge to pattern-recognition algorithms since the input patterns (galaxy redshift…

Astrophysics · Physics 2007-05-23 Nicholas G. Phillips , A. Kogut

This paper presents a deep learning-based de-homogenization method for structural compliance minimization. By using a convolutional neural network to parameterize the mapping from a set of lamination parameters on a coarse mesh to a…

Machine Learning · Computer Science 2021-11-03 Martin O. Elingaard , Niels Aage , J. Andreas Bærentzen , Ole Sigmund

Recently, deep learning methods such as the convolutional neural networks have gained prominence in the area of image denoising. This is owing to their proven ability to surpass state-of-the-art classical image denoising algorithms such as…

Image and Video Processing · Electrical Eng. & Systems 2024-09-02 Basit O. Alawode , Mudassir Masood

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

Astrophysics · Physics 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

In this third paper in a series, we investigate the need of spectra denoising for the derivation of stellar parameters. We have used two distinct datasets for this work. The first one contains spectra in the range of 4450-5400 {\AA} at a…

Solar and Stellar Astrophysics · Physics 2024-12-09 Marwan Gebran , Ian Bentley , Rose Brienza , Frédéric Paletou

Dark matter cannot be observed directly, but its weak gravitational lensing slightly distorts the apparent shapes of background galaxies, making weak lensing one of the most promising probes of cosmology. Several observational studies have…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-18 Dezső Ribli , Bálint Ármin Pataki , István Csabai