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Related papers: Fast Multipole Method for Gravitational Lensing. A…

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Gravitational lensing of fast radio bursts (FRBs) offers an exciting avenue for several cosmological applications. However, it is not yet clear how many such events future surveys will detect nor how to optimally find them. We use the known…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Liam Connor , Vikram Ravi

Quantifying image distortions caused by strong gravitational lensing and estimating the corresponding matter distribution in lensing galaxies has been primarily performed by maximum likelihood modeling of observations. This is typically a…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Yashar D. Hezaveh , Laurence Perreault Levasseur , Philip J. Marshall

Matrix multiplication (GEMM) is a core operation to numerous scientific applications. Traditional implementations of Strassen-like fast matrix multiplication (FMM) algorithms often do not perform well except for very large matrix sizes, due…

Mathematical Software · Computer Science 2016-11-04 Jianyu Huang , Leslie Rice , Devin A. Matthews , Robert A. van de Geijn

We present a new approach for fast calculation of gravitational lensing properties, including the lens potential, deflection angles, convergence, and shear, of elliptical Navarro-Frenk-White (NFW) and Hernquist density profiles, by…

Instrumentation and Methods for Astrophysics · Physics 2021-08-04 Masamune Oguri

The microlensing effect has developed into a powerful technique for a diverse range of applications including exoplanet discoveries, structure of the Milky Way, constraints on MAssive Compact Halo Objects, and measurements of the size and…

Astrophysics of Galaxies · Physics 2021-12-22 Xuechun Chen , Yiping Shu , Guoliang Li , Wenwen Zheng

Fast scanning probe microscopy enabled via machine learning allows for a broad range of nanoscale, temporally resolved physics to be uncovered. However, such examples for functional imaging are few in number. Here, using piezoresponse force…

We present here an alternative method for calculating magnifications in gravitational lensing calculations -- the Ray Bundle method. We provide a detailed comparison between the distribution of magnifications obtained compared with analytic…

Astrophysics · Physics 2009-10-31 C. J. Fluke , R. L. Webster , Daniel J. Mortlock

We use the large cosmological Millennium Simulation (MS) to construct the first all-sky maps of the lensing potential and the deflection angle, aiming at gravitational lensing of the CMB, with the goal of properly including small-scale…

The Fast Multipole Method (FMM) is an efficient numerical algorithm for computation of long-ranged forces in $N$-body problems within gravitational and electrostatic fields. This method utilizes multipole expansions of the Green's function…

Machine Learning · Computer Science 2025-09-26 Emilio McAllister Fognini , Marta M. Betcke , Ben T. Cox

Gravitational lensing calculation using a direct inverse ray-shooting approach is a computationally expensive way to determine magnification maps, caustic patterns, and light-curves (e.g. as a function of source profile and size). However,…

Instrumentation and Methods for Astrophysics · Physics 2009-09-28 Alexander C. Thompson , Christopher J. Fluke , David G. Barnes , Benjamin R. Barsdell

The 0th order of affine perturbation series of the deflection angle of a ray near a photon sphere is more accurate than a deflection angle in a strong deflection limit, which is used often, because the later has hidden error terms. We…

General Relativity and Quantum Cosmology · Physics 2023-04-14 Naoki Tsukamoto

The eikonal equation is instrumental in many applications in several fields ranging from computer vision to geoscience. This equation can be efficiently solved using the iterative Fast Sweeping (FS) methods and the direct Fast Marching (FM)…

Computational Engineering, Finance, and Science · Computer Science 2016-08-30 Eran Treister , Eldad Haber

In boundary element methods (BEM) in $\mathbb{R}^3$, matrix elements and right hand sides are typically computed via analytical or numerical quadrature of the layer potential multiplied by some function over line, triangle and tetrahedral…

Numerical Analysis · Mathematics 2023-04-06 Nail A. Gumerov , Shoken Kaneko , Ramani Duraiswami

Dedicated 'Stage IV' observatories will soon observe the entire extragalactic sky, to measure the 'cosmic shear' distortion of galaxy shapes by weak gravitational lensing. To measure the apparent shapes of those galaxies, we present an…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-08 Xiangchong Li , Yin Li , Richard Massey

Statistical analyses of observed galaxy distortions are often used to reconstruct the mass distribution of an intervening cluster responsible for gravitational lensing. In current projects, distortions of thousands of source galaxies have…

Astrophysics · Physics 2007-05-23 Marco Lombardi , Giuseppe Bertin

High-performance learned image compression codecs require flexible probability models to fit latent representations. Gaussian Mixture Models (GMMs) were proposed to satisfy this demand, but suffer from a significant runtime performance…

Image and Video Processing · Electrical Eng. & Systems 2025-09-24 Shimon Murai , Fangzheng Lin , Jiro Katto

In recent study in Ref.[7] (arXiv: 2401.12525), we have introduced a method aimed at calculating the weak-field asymptotic deflection angle. This method offers an efficient computational approach that avoids the complexities of integration…

General Relativity and Quantum Cosmology · Physics 2024-02-02 Zonghai Li

We present GOFMM (geometry-oblivious FMM), a novel method that creates a hierarchical low-rank approximation, "compression," of an arbitrary dense symmetric positive definite (SPD) matrix. For many applications, GOFMM enables an approximate…

Numerical Analysis · Computer Science 2017-07-04 Chenhan D. Yu , James Levitt , Severin Reiz , George Biros

Strong gravitational lensing provides a purely gravitational means to infer properties of dark matter halos and thereby constrain the particle nature of dark matter. Strong lenses sometimes appear as four lensed images of a background…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Daniel Gilman , Simon Birrer , Anna Nierenberg , Maverick S. H. Oh

We describe how gravitational lensing of fast radio bursts (FRBs) is affected by a plasma screen in the vicinity of the lens or somewhere between the source and the observer. Wave passage through a turbulent medium affects gravitational…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Pawan Kumar , Paz Beniamini