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This paper presents a systematic literature review focusing on the application of machine learning techniques for deriving observational constraints in cosmology. The goal is to evaluate and synthesize existing research to identify…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Luis Rojas , Sebastián Espinoza , Esteban González , Carlos Maldonado , Fei Luo

Studies of disordered heterogeneous media and galaxy cosmology share a common goal: analyzing the distribution of particles at `microscales' to predict physical properties at `macroscales', whether for a liquid, composite material, or…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Oliver H. E. Philcox , Salvatore Torquato

We develop a spectrally accurate numerical method to compute solutions of a model partial differential equation used in plasma physics to describe diffusion in velocity space due to Fokker-Planck collisions. The solution is represented as a…

Classical Analysis and ODEs · Mathematics 2015-03-18 Jon Wilkening , Antoine Cerfon

Constraints on cosmological parameters from large-scale structure have traditionally been obtained from two-point statistics. However, non-linear structure formation renders these statistics insufficient in capturing the full information…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Alex Hall , Alexander Mead

Inspired by a series of remarkable papers in recent years that use Deep Neural Nets to substantially speed up the calibration of pricing models, we investigate the use of Chebyshev Tensors instead of Deep Neural Nets. Given that Chebyshev…

Risk Management · Quantitative Finance 2020-12-21 Mariano Zeron , Ignacio Ruiz

Cosmological perturbation theory is a powerful tool to predict the statistics of large-scale structure in the weakly non-linear regime, but even at 1-loop order it results in computationally expensive mode-coupling integrals. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-17 Xiao Fang , Jonathan A. Blazek , Joseph E. McEwen , Christopher M. Hirata

We propose an analytic procedure that allows to determine quantitatively the deviation in the behavior of cosmological perturbations between a given f(R) modified gravity model and a LCDM reference model. Our method allows to study…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Daniele Bertacca , Nicola Bartolo , Sabino Matarrese

This paper deals with the time evolution in the matter era of perturbations in Friedman-Lemaitre models with arbitrary density parameter $\Omega$, with either a zero cosmological constant, $\Lambda = 0$, or with a non-zero cosmological…

Astrophysics · Physics 2011-05-23 F. R. Bouchet , S. Colombi , E. Hivon , R. Juszkiewicz

Recent cosmological tensions pose difficulties for $\Lambda$CDM. Forthcoming facilities will be able to check whether these tensions result from systematic effects or indeed with the $\Lambda$CDM model itself. However, these new data will…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-12 Dinko Milaković , John K. Webb

Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z$\simeq 10^7$. Unfortunately all the attempts so far carried out…

Instrumentation and Methods for Astrophysics · Physics 2017-02-22 Giorgio Sironi

The longstanding search for the cosmological model that best describes the Universe has been made more intriguing since the recent discovery of the Hubble constant, $H_{0}$, tension observed between the value of $H_{0}$ from the Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 G. Bargiacchi , M. G. Dainotti , S. Capozziello

Prompted by the recent more precise determination of the basic cosmological parameters and growing evidence that the matter-energy content of the universe is now dominated by dark energy and dark matter we present the general solution of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Marek Demianski , Zdzislaw A. Golda , Andrzej Woszczyna

We consider a series of distorted black hole initial data sets, and develop techniques to evolve them using the linearized equations of motion for the gravitational wave perturbations on a Schwarzschild background. We apply this to 2D and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Gabrielle Allen , Karen Camarda , Edward Seidel

The strongest evidence for dark energy comes presently from geometric techniques such as the supernova distance-redshift relation. By combining the measured expansion history with the Friedmann equation one determines the energy density and…

Astrophysics · Physics 2008-11-26 Edmund Bertschinger

We consider discrete linear Chebyshev approximation problems in which the unknown parameters of linear function are fitted by minimizing the maximum absolute deviation of errors. Such problems find application in the solution of…

Optimization and Control · Mathematics 2020-12-22 Nikolai Krivulin

Possible explanations of the observed accelerated expansion of the Universe are the introduction of a dark energy component or the modifications of gravity at large distances. A particular difference between these scenarios is the dynamics…

Astrophysics · Physics 2007-05-23 Jia-Yu Tang , Jochen Weller , Alan Zablocki

The basic question in perturbation analysis of Markov chains is: how do small changes in the transition kernels of Markov chains translate to chains in their stationary distributions? Many papers on the subject have shown, roughly, that the…

Probability · Mathematics 2025-08-13 Na Lin , Yuanyuan Liu , Aaron Smith

This paper presents for the first time a robust exact line-search method based on a full pseudospectral (PS) numerical scheme employing orthogonal polynomials. The proposed method takes on an adaptive search procedure and combines the…

Optimization and Control · Mathematics 2023-03-06 Kareem T. Elgindy

The purpose of this study is to utilize the Chebyshev spectral method neural network(CSNN) model to solve differential equations. This approach employs a single-layer neural network wherein Chebyshev spectral methods are used to construct…

Numerical Analysis · Mathematics 2024-07-08 Pengsong Yin , Shuo Ling , Wenjun Ying

We develop a perturbative model to describe large-scale structure in cosmologies where dark matter consists of a mixture of cold (CDM) and warm (WDM) components. In such mixed dark matter (MDM) scenarios, even a subdominant warm component…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-11 Şafak Çelik , Fabian Schmidt