Accession Number : ADA189804

Title :   The Fast Multiple Method for Gridless Particle Simulations.

Descriptive Note : Research rept.,

Corporate Author : YALE UNIV NEW HAVEN CT DEPT OF COMPUTER SCIENCE

Personal Author(s) : Ambrosiano, J ; Greengard, L ; Rokhlin, V

PDF Url : ADA189804

Report Date : Sep 1987

Pagination or Media Count : 18

Abstract : The numerical solution of the N- body problem is gravitation and electrostatics has traditionally been obtained via particle-in-cell methods (PIC) since direct evaluation of all pairwise interparticle forces, requiring 0(N-sq) operations, is too expensive. Recently, hierarchical solvers, which use data structures and lumped-force approximations, have made gridless simulations possible in O(N-log(N)) operations. In this paper, we explore the use of the fast multipole method (FMM) - a highly accurate order 0(N) algorithm - in particle simulations. The FMM is described with its relation to other methods. Technical considerations of gridless simulations such as discrete particle fluctuations, sampling errors and boundary conditions are discussed and compared with PIC methodology. Examples of electrostatic simulations in plasma physics are presented.

Descriptors :   *ELECTROSTATICS, *PLASMAS(PHYSICS), *N BODY PROBLEM, *NUMERICAL METHODS AND PROCEDURES, BOUNDARIES, DATA BASES, ERRORS, NUMERICAL ANALYSIS, PARTICLES, SAMPLING, SIMULATION, SOLUTIONS(GENERAL), GRIDS

Subject Categories : Numerical Mathematics
      Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE