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The Dark Matter present in the Large-Scale Structure of the Universe is invisible, but its presence can be inferred through the small gravitational lensing effect it has on the images of far away galaxies. By measuring this lensing effect…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Benjamin Remy , Francois Lanusse , Zaccharie Ramzi , Jia Liu , Niall Jeffrey , Jean-Luc Starck

In this study, we investigate the impact of covariance within uncertainties on the inference of cosmological and astrophysical parameters, specifically focusing on galaxy stellar mass functions derived from the CAMELS simulation suite.…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-30 Yongseok Jo , Shy Genel , Joel Leja , Benjamin Wandelt

Machine learning (ML) methods are extraordinarily successful at denoising photographic images. The application of such denoising methods to scientific images is, however, often complicated by the difficulty in experimentally obtaining a…

The unprecedented amount and the excellent quality of lensing data that the upcoming ground- and space-based surveys will produce represent a great opportunity to shed light on the questions that still remain unanswered concerning our…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Carolina Parroni , Edouard Tollet , Vincenzo F. Cardone , Roberto Maoli , Roberto Scaramella

Covariance and histogram image descriptors provide an effective way to capture information about images. Both excel when used in combination with special purpose distance metrics. For covariance descriptors these metrics measure the…

Machine Learning · Statistics 2015-05-26 Matt J. Kusner , Nicholas I. Kolkin , Stephen Tyree , Kilian Q. Weinberger

We compare the measurements of the bispectrum and the estimate of its covariance obtained from a set of different methods for the efficient generation of approximate dark matter halo catalogs to the same quantities obtained from full N-body…

The interpretation of cosmological observables requires the use of increasingly sophisticated theoretical models. Since these models are becoming computationally very expensive and display non-trivial uncertainties, the use of standard…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Marcos Pellejero-Ibañez , Raul E. Angulo , Giovanni Aricó , Matteo Zennaro , Sergio Contreras , Jens Stücker

(Abridged) Combining cosmic shear power spectra and cluster counts is powerful to improve cosmological parameter constraints and/or test inherent systematics. However they probe the same cosmic mass density field, if the two are drawn from…

Astrophysics · Physics 2009-06-23 Masahiro Takada , Sarah Bridle

Denoising score matching (DSM) provides a way to learn data distributions by training a neural network to recover the score function, defined as the gradient of the log density, from noise-corrupted samples. Once trained, the score…

Machine Learning · Computer Science 2026-05-11 Victor Livernoche , Jie Zan , Reihaneh Rabbany

Compressed Sensing suggests that the required number of samples for reconstructing a signal can be greatly reduced if it is sparse in a known discrete basis, yet many real-world signals are sparse in a continuous dictionary. One example is…

Information Theory · Computer Science 2015-07-24 Yuanxin Li , Yuejie Chi

Probing properties of neutron stars from photometric observations of these objects helps us answer crucial questions at the forefront of multi-messenger astronomy, such as, what is behavior of highest density matter in extreme environments…

High Energy Astrophysical Phenomena · Physics 2025-10-22 Abu Bucker Siddik , Diane Oyen , Soumi De , Greg Olmschenk , Constantinos Kalapotharakos

Extracting accurate cosmological information from galaxy-galaxy and galaxy-matter correlation functions on non-linear scales ($\lesssim 10 h^{-1} \mathrm{Mpc}$) requires cosmological simulations. Additionally, one has to marginalise over…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Johannes U. Lange , Frank C. van den Bosch , Andrew R. Zentner , Kuan Wang , Andrew P. Hearin , Hong Guo

We investigate the bias and error in estimates of the cosmological parameter covariance matrix, due to sampling or modelling the data covariance matrix, for likelihood width and peak scatter estimators. We show that these estimators do not…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Andy Taylor , Benjamin Joachimi

Image denoising is still a challenging issue in many computer vision sub-domains. Recent studies show that significant improvements are made possible in a supervised setting. However, few challenges, such as spatial fidelity and…

Computer Vision and Pattern Recognition · Computer Science 2022-07-13 Masud An Nur Islam Fahim , Nazmus Saqib , Shafkat Khan Siam , Ho Yub Jung

Deep neural networks trained on biased data often inadvertently learn unintended inference rules, particularly when labels are strongly correlated with biased features. Existing bias mitigation methods typically involve either a)…

Computer Vision and Pattern Recognition · Computer Science 2024-10-22 Rajeev Ranjan Dwivedi , Priyadarshini Kumari , Vinod K Kurmi

We consider high-dimensional measurement errors with high-frequency data. Our objective is on recovering the high-dimensional cross-sectional covariance matrix of the random errors with optimality. In this problem, not all components of the…

Statistics Theory · Mathematics 2024-04-03 Jinyuan Chang , Qiao Hu , Cheng Liu , Cheng Yong Tang

This paper introduces a new approach to reconstruct cosmological functions using artificial neural networks based on observational measurements with minimal theoretical and statistical assumptions. By using neural networks, we can generate…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-24 Isidro Gómez-Vargas , Ricardo Medel Esquivel , Ricardo García-Salcedo , J. Alberto Vázquez

Compared with traditional seismic noise attenuation algorithms that depend on signal models and their corresponding prior assumptions, removing noise with a deep neural network is trained based on a large training set, where the inputs are…

Geophysics · Physics 2019-07-23 Siwei Yu , Jianwei Ma , Wenlong Wang

Over $90$\% of dark matter haloes in cosmological simulations have unresolved properties. This can hinder the dynamical range of simulations and result in systematic biases when modelling cosmological tracers. We aim to more precisely…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-27 Sujatha Ramakrishnan , Violeta Gonzalez-Perez , Gabriele Parimbelli , Gustavo Yepes

Recovering a low-rank signal matrix from its noisy observation, commonly known as matrix denoising, is a fundamental inverse problem in statistical signal processing. Matrix denoising methods are generally based on shrinkage or thresholding…

Methodology · Statistics 2017-01-23 Santosh Kumar Yadav , Rohit Sinha , Prabin Kumar Bora