论文标题
用于宇宙N体模拟的混合快速多极方法
A Hybrid Fast Multipole Method for Cosmological N-body Simulations
论文作者
论文摘要
我们研究了一种旨在针对正在进行和未来的高贵重天空调查的大规模宇宙n体型模拟的混合数值算法。它利用截短的快速多种方法（FMM）进行短距离重力，并与粒子网（PM）方法结合起来，以实现远距离电位，该方法用于处理极大的粒子数。在这项工作中，我们提出了一种特定的策略，可以通过高斯形因子修改常规FMM，并为多极扩展之间的相互作用内核提供定量表达式。此外，引入了杂种方法的适当多极接受标准，以解决截断引起的潜在精度损失。此类过程比原始的FMM减少了计算的安装，并使全球通信脱离了计算。引入了简化版本的代码，以验证混合算法，准确性和并行实现。
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, incorporating with a Particle Mesh (PM) method for long-range potential, which is applied to deal with extremely large particle number. In this work, we present a specific strategy to modify a conventional FMM by a Gaussian shaped factor and provide quantitative expressions for the interaction kernels between multipole expansions. Moreover, a proper multipole acceptance criteria for the hybrid method is introduced to solve potential precision loss induced by the truncation. Such procedures reduce the mount of computation than an original FMM and decouple the global communication. A simplified version of code is introduced to verify the hybrid algorithm, accuracy and parallel implementation.
