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

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We demonstrate an efficient method to compute the strong-gravitational-lensing deflection angle and magnification for any elliptical surface-density profile. This method solves a numerical hurdle in lens modelling that has lacked a general…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-10 Anowar J. Shajib

This paper explores a key question in numerical linear algebra: how can we compute projectors onto the deflating subspaces of a regular matrix pencil $(A,B)$, in particular without using matrix inversion or defaulting to an expensive Schur…

Numerical Analysis · Mathematics 2026-01-21 James Demmel , Ioana Dumitriu , Ryan Schneider

We present a fast algorithm for computing the diffracted field from arbitrary binary (sharp-edged) planar apertures and occulters in the scalar Fresnel approximation, for up to moderately high Fresnel numbers ($\lesssim 10^3$). It uses a…

Instrumentation and Methods for Astrophysics · Physics 2020-12-18 Alex H. Barnett

The Gibbons-Werner method for calculating deflection angles using the Gauss-Bonnet theorem and optical/Jacobi metric has become widely popular in recent years. Werner extended this method to stationary spacetimes, where the optical/Jacobi…

General Relativity and Quantum Cosmology · Physics 2025-03-18 Zonghai Li

Fourier ptychographic microscopy (FPM) is a recently developed computational imaging technique for wide-field, high-resolution microscopy with a high space-bandwidth product. It integrates the concepts of synthetic aperture and phase…

Optics · Physics 2021-12-30 Chuanjian Zheng , Shaohui Zhang , Guocheng Zhou , Yao Hu , Qun Hao

We propose a novel technique to refine the modelling of galaxy clusters mass distribution using gravitational lensing. The idea is to combine the strengths of both "parametric" and "non-parametric" methods to improve the quality of the fit.…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Eric Jullo , Jean-Paul Kneib

In micromagnetic simulations, the demagnetization field is by far the computationally most expensive field component and often a limiting factor in large multilayer systems. We present an exact method to calculate the demagnetization field…

Computational Physics · Physics 2020-03-18 Paul Heistracher , Florian Bruckner , Claas Abert , Christoph Vogler , Dieter Suess

Time-delay cosmography in strongly lensed quasars offer an independent way of measuring the Hubble constant, $H_0$. However, it has been proposed that the combination of microlensing and source-size effects, also known as microlensing time…

Astrophysics of Galaxies · Physics 2021-03-24 J. H. H. Chan , K. Rojas , M. Millon , F. Courbin , V. Bonvin , G. Jauffret

Recent quantitative parameter mapping methods including MR fingerprinting (MRF) collect a time series of images that capture the evolution of magnetization. The focus of this work is to introduce a novel approach termed as Deep Factor…

Computer Vision and Pattern Recognition · Computer Science 2023-04-04 Yan Chen , James H. Holmes , Curtis Corum , Vincent Magnotta , Mathews Jacob

Accurate real-time simulation of lens optics remains challenging due to the computational expense of full ray tracing and the limitations of existing approximations. The commonly used pinhole model and thin-lens model ignore many optical…

Graphics · Computer Science 2026-05-06 Yang Chen , Xiaochun Tong , Afet Abzar , Leo Hanxu , Matthew Avolio , Toshiya Hachisuka

Cosmological gravitational microlensing is a useful technique for understanding the structure of the inner parts of a quasar, especially the accretion disk and the central supermassive black hole. So far, most of the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Georgios Vernardos , Christopher J. Fluke

Fast radio bursts (FRBs) represent an exciting frontier in the study of gravitational lensing, due to their brightness, extragalactic nature, and the compact, coherent characteristics of their emission. In a companion work [Kader,…

We present a new approach to gravitational lens massmap reconstruction. Our massmap solutions perfectly reproduce the positions, fluxes, and shears of all multiple images. And each massmap accurately recovers the underlying mass…

Astrophysics · Physics 2009-11-13 D. Coe , E. Fuselier , N. Benitez , T. Broadhurst , B. Frye , H. Ford

Pansharpening aims to generate high-resolution multispectral (HRMS) images by fusing low-resolution multispectral (LRMS) and high-resolution panchromatic (PAN) images while preserving both spectral and spatial information. Although deep…

Computer Vision and Pattern Recognition · Computer Science 2026-04-13 Zhiqi Yang , Jin-Liang Xiao , Shan Yin , Liang-Jian Deng , Gemine Vivone

We describe and demonstrate the potential of a new and very efficient method for simulating certain classes of modified gravity theories, such as the widely studied $f(R)$ gravity models. High resolution simulations for such models are…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-14 Sownak Bose , Baojiu Li , Alexandre Barreira , Jian-hua He , Wojciech A. Hellwing , Kazuya Koyama , Claudio Llinares , Gong-Bo Zhao

The recently discovered fast radio bursts (FRBs), presumably of extra-galactic origin, have the potential to become a powerful probe of the intergalactic medium (IGM). We point out a few such potential applications. We provide expressions…

High Energy Astrophysical Phenomena · Physics 2015-12-29 Z. Zheng , E. O. Ofek , S. R. Kulkarni , J. D. Neill , M. Juric

Many applications and algorithms in the field of gravitational lensing make use of meshes with a finite number of nodes to analyze and manipulate data. Specific examples in lensing are astronomical CCD images in general, the reconstruction…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Julian Merten

Scalar diffraction calculations such as the angular spectrum method (ASM) and Fresnel diffraction, are widely used in the research fields of optics, X-rays, electron beams, and ultrasonics. It is possible to accelerate the calculation using…

This research explored a novel explicit total Lagrangian Fragile Points Method (FPM) for finite deformation of hyperelastic materials. In contrast to mesh-based methods, where mesh distortion may pose numerical challenges, meshless methods…

We investigate the chance of detecting proto-planetary or debris disks in stars that induce microlensing events (lenses). The modification of the light curves shapes due to occultation and extinction by the disks as well as the additional…

Earth and Planetary Astrophysics · Physics 2015-05-13 M. Hundertmark , F. V. Hessman , S. Dreizler