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Related papers: Generalised quasi-linear approximation of the HMRI

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The linear coefficient in a partially linear model with confounding variables can be estimated using double machine learning (DML). However, this DML estimator has a two-stage least squares (TSLS) interpretation and may produce overly wide…

Methodology · Statistics 2022-01-03 Corinne Emmenegger , Peter Bühlmann

Deep learning models have been shown to outperform methods that rely on summary statistics, like the power spectrum, in extracting information from complex cosmological data sets. However, due to differences in the subgrid physics…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-16 Andrea Roncoli , Aleksandra Ćiprijanović , Maggie Voetberg , Francisco Villaescusa-Navarro , Brian Nord

In this paper, we propose a dynamical low-rank (DLR) approximation framework for solving the semiclassical Schrodinger equation with uncertainties. The primary numerical challenges arise from the dual nature of the oscillations: the spatial…

Numerical Analysis · Mathematics 2026-02-23 Liu Liu , Limin Xu , Zhenyi Zhu

We present a new framework for characterizing quasinormal modes (QNMs) or resonant states for the wave equation on asymptotically flat spacetimes, applied to the setting of extremal Reissner-Nordstr\"om black holes. We show that QNMs can be…

General Relativity and Quantum Cosmology · Physics 2021-10-15 Dejan Gajic , Claude Warnick

Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique that estimates magnetic susceptibility of tissue from Larmor frequency offset measurements. The generation of QSM requires solving a challenging…

Medical Physics · Physics 2020-08-18 Juan Liu , Kevin M. Koch

Stochastic gradient descent and other first-order variants, such as Adam and AdaGrad, are commonly used in the field of deep learning due to their computational efficiency and low-storage memory requirements. However, these methods do not…

Optimization and Control · Mathematics 2025-02-19 Aditya Ranganath , Mukesh Singhal , Roummel Marcia

We study a distributed beamforming approach for cell-free massive multiple-input multiple-output networks, referred to as Global Statistics & Local Instantaneous information-based minimum mean-square error (GSLI-MMSE). The scenario with…

Signal Processing · Electrical Eng. & Systems 2026-02-05 Zhe Wang , Emil Björnson , Jiayi Zhang , Peng Zhang , Vitaly Petrov , Bo Ai

Using direct numerical simulations (DNS) we verify that in the kinematic regime, a turbulent helical dynamo grows in such a way that the magnetic energy spectrum remains to high precision shape-invariant, i.e., at each wavenumber $k$ the…

Astrophysics of Galaxies · Physics 2014-10-24 Kandaswamy Subramanian , Axel Brandenburg

We present dynamos computed using a hybrid QG-3D numerical scheme in a thick spherical shell geometry. Our model is based on a quasi-geostrophic convection code extended with a 3D treatment of heat transport and magnetic induction. We find…

Geophysics · Physics 2023-12-18 Olivier Barrois , Thomas Gastine , Christopher C. Finlay

Quasi-normal mode (QNM) modeling is an invaluable tool for characterizing remnant black holes, studying strong gravity, and testing GR. Only recently have QNM studies begun to focus on multimode fitting to numerical relativity (NR) strain…

Accretion of magnetized gas on compact astrophysical objects such as black holes has been successfully modeled using general relativistic magnetohydrodynamic (GRMHD) simulations. These simulations have largely been performed in the Kerr…

High Energy Astrophysical Phenomena · Physics 2024-03-07 Prashant Kocherlakota , Ramesh Narayan , Koushik Chatterjee , Alejandro Cruz-Osorio , Yosuke Mizuno

This paper develops the asymptotic theory of a Fully Modified Generalized Least Squares estimator for multivariate cointegrating polynomial regressions. Such regressions allow for deterministic trends, stochastic trends and integer powers…

Econometrics · Economics 2020-08-10 Yicong Lin , Hanno Reuvers

Deep learning (DL)-based general circulation models (GCMs) are emerging as fast simulators, yet their ability to replicate extreme events outside their training range remains unknown. Here, we evaluate two such models -- the hybrid Neural…

Atmospheric and Oceanic Physics · Physics 2025-10-28 Zilu Meng , Gregory J. Hakim , Wenchang Yang , Gabriel A. Vecchi

Results of numerical simulations obtained by a staggered finite difference scheme together with an efficient immersed boundary method are presented to understand the effects of the shape of three-dimensional obstacles on the transition of a…

Fluid Dynamics · Physics 2015-03-31 Paolo Orlandi , Sergio Pirozzoli , Matteo Bernardini

While standard approaches to quantum simulation require a number of qubits proportional to the number of simulated particles, current noisy quantum computers are limited to tens of qubits. With the technique of holographic quantum…

Quantum Physics · Physics 2024-03-07 Sajant Anand , Johannes Hauschild , Yuxuan Zhang , Andrew C. Potter , Michael P. Zaletel

In this work, quasinormal modes (QNMs) of the Schwarzschild black hole are investigated by taking into account the quantum fluctuations. Gravitational and Dirac perturbations were considered for this case. The Regge-Wheeler gauge and the…

General Relativity and Quantum Cosmology · Physics 2016-04-05 Mahamat Saleh , Bouetou Bouetou Thomas , Kofané Timoléon Crépin

In this paper, we study the constraints on the $f(Q)=Q/(8\pi G) - \alpha \ln(Q/Q_0)$, symmetric teleparallel model using local measurements and gravitational wave mock standard sirens. Using observational local SNIa and BAO data and energy…

General Relativity and Quantum Cosmology · Physics 2023-08-14 José Antonio Nájera , Carlos Aráoz Alvarado , Celia Escamilla-Rivera

We calculate analytically the highly damped quasinormal mode spectra of generic single-horizon black holes using the rigorous WKB techniques of Andersson and Howls\cite{Andersson}. We thereby provide a firm foundation for previous analysis,…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Ramin G. Daghigh , Gabor Kunstatter

Data fields sampled on irregularly spaced points arise in many applications in the sciences and engineering. For regular grids, Convolutional Neural Networks (CNNs) have been successfully used to gaining benefits from weight sharing and…

Machine Learning · Computer Science 2023-02-28 Nathaniel Trask , Ravi G. Patel , Ben J. Gross , Paul J. Atzberger

Analysis of biological rhythm data often involves performing least squares trigonometric regression, which models the oscillations of a response over time as a sum of sinusoidal components. When the response is not normally distributed, an…

Applications · Statistics 2026-01-19 Michael T. Gorczyca