English
Related papers

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

200 papers

In this paper, we present a spherical Fast Multipole Method (sFMM) for ray tracing simulation of gravitational lensing (GL) on a curved sky. The sFMM is a non-trivial extension of the Fast Multiple Method (FMM) to sphere $\mathbb S^2$, and…

Instrumentation and Methods for Astrophysics · Physics 2023-05-17 Xingpao Suo , Xi Kang , Chengliang Wei , Guoliang Li

The approximate computation of all gravitational forces between $N$ interacting particles via the fast multipole method (FMM) can be made as accurate as direct summation, but requires less than $\mathcal{O}(N)$ operations. FMM groups…

Instrumentation and Methods for Astrophysics · Physics 2014-05-12 Walter Dehnen

This article introduces a new fast direct solver for linear systems arising out of wide range of applications, integral equations, multivariate statistics, radial basis interpolation, etc., to name a few. \emph{The highlight of this new…

Numerical Analysis · Mathematics 2014-07-08 Sivaram Ambikasaran , Eric Darve

The long-range magnetic field is the most time-consuming part in micromagnetic simulations. Improvements both on a numerical and computational basis can relief problems related to this bottleneck. This work presents an efficient…

Computational Physics · Physics 2017-08-23 Pietro Palmesi , Lukas Exl , Florian Bruckner , Claas Abert , Dieter Suess

I describe a modification to the original Fast Multipole Method (FMM) of Greengard & Rokhlin that approximates the gravitation field of an FMM cell as a small uniform grid (a "gridlet") of effective masses. The effective masses on a gridlet…

Computational Physics · Physics 2019-07-31 Nickolay Y. Gnedin

We have developed a new three-dimensional algorithm, based on the standard P$^3$M method, for computing deflections due to weak gravitational lensing. We compare the results of this method with those of the two-dimensional planar approach,…

Astrophysics · Physics 2009-10-31 H. M. P. Couchman , Andrew J. Barber , Peter A. Thomas

We present a new and very fast method for producing microlensing magnification maps at high optical depths. It is based on the combination of two approaches: (a) the two-dimensional Poisson solver for a deflection potential and (b) inverse…

Instrumentation and Methods for Astrophysics · Physics 2021-09-22 V. N. Shalyapin , R. Gil-Merino , L. J. Goicoechea

The fast multipole method (FMM) has received growing attention in the beam physics simulation. In this study, we formulate an interpolation-based FMM for the computation of the relativistic space-charge field. Different to the…

Computational Physics · Physics 2023-07-19 Yi-Kai Kan , Franz X. Kärtner , Sabine Le Borne , Jens-Peter M. Zemke

Strong gravitational lensing by irregular mass distributions, such as galaxy clusters, is generally not well quantified by cross sections of analytic mass models. Computationally expensive ray-tracing methods have so far been necessary for…

Astrophysics · Physics 2016-08-30 C. Fedeli , M. Meneghetti , M. Bartelmann , K. Dolag , L. Moscardini

We investigate a hybrid numerical algorithm aimed at the large-scale cosmological N-body simulation for the on-going and the future high precious sky surveys. It makes use of a truncated Fast Multiple Method (FMM) for short-range gravity,…

Computational Physics · Physics 2021-01-13 Qiao Wang

Modern applications of strong gravitational lensing require the ability to use precise and varied observational data to constrain complex lens models. I discuss two sets of computational methods for lensing calculations. The first is a new…

Astrophysics · Physics 2007-05-23 Charles R. Keeton

The Fast Multipole Method (FMM) provides a highly efficient computational tool for solving constant coefficient partial differential equations (e.g. the Poisson equation) on infinite domains. The solution to such an equation is given as the…

Numerical Analysis · Mathematics 2012-01-04 A. Gillman , P. G. Martinsson

We present an improved inverse ray-shooting code based on GPUs for generating microlensing magnification maps. In addition to introducing GPUs for acceleration, we put the efforts in two aspects: (i) A standard circular lens plane is…

Instrumentation and Methods for Astrophysics · Physics 2022-06-08 Wenwen Zheng , Xuechun Chen , Guoliang Li , Hou-zun Chen

The meshless/meshfree radial basis function (RBF) method is a powerful technique for interpolating scattered data. But, solving large RBF interpolation problems without fast summation methods is computationally expensive. For RBF…

Numerical Analysis · Mathematics 2016-06-27 Wei Zhao , Martin Stoll

While fast multipole methods (FMMs) are in widespread use for the rapid evaluation of potential fields governed by the Laplace, Helmholtz, Maxwell or Stokes equations, their coupling to high-order quadratures for evaluating layer potentials…

Numerical Analysis · Mathematics 2021-04-26 Leslie Greengard , Michael O'Neil , Manas Rachh , Felipe Vico

An implementation of the fast multiple method (FMM) is performed for magnetic systems with long-ranged dipolar interactions. Expansion in spherical harmonics of the original FMM is replaced by expansion of polynomials in Cartesian…

Computational Physics · Physics 2015-05-13 Wen Zhang , Stephan Haas

We describe a accurate and fast pixel-based statistical method to interpolate fields of arbitrary spin on the sphere. We call this method Fast and Lean Interpolation on the Sphere (FLINTS). The method predicts the optimal interpolated…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-21 Guilhem Lavaux , Benjamin D. Wandelt

We introduce the Fast Free Memory method (FFM), a new fast method for the numerical evaluation of convolution products. Inheriting from the Fast Multipole Method, the FFM is a descent-only and kernel-independent algorithm. We give the…

Numerical Analysis · Mathematics 2019-09-13 Matthieu Aussal , Marc Bakry

The Fast Multipole Method (FMM) for the Poisson equation is extended to the case of non-axisymmetric problems in an axisymmetric domain, described by cylindrical coordinates. The method is based on a Fourier decomposition of the source into…

Numerical Analysis · Mathematics 2023-01-04 Michael J. Carley

Gravitational waves (GWs) exhibit wave-optics effects when their wavelength is comparable to the scale of the gravitational lens. This may occur in lensing from galactic subhalos in GWs emitted by binary black-hole mergers, and is gaining…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-16 Nino Ephremidze , Marc Kamionkowski , Cora Dvorkin
‹ Prev 1 2 3 10 Next ›