一种用于宇宙学N体模拟的混合快速多极方法
A Hybrid Fast Multipole Method for Cosmological N-body Simulations
摘要：
本文研究了一种用于大尺度宇宙学N体模拟的混合数值算法，该算法适用于当前和未来的高精度巡天观测。它采用截断快速多重方法（FMM）的短程重力，结合粒子网格（PM）方法的远程位，这是适用于处理非常大的粒子数。在这项工作中，我们提出了一个特定的策略，修改传统的FMM的高斯形因子，并提供定量的表达多极展开之间的相互作用内核。此外，适当的多极接受准则的混合方法，以解决潜在的截断引起的精度损失。这样的程序减少了计算量比原来的FMM和解耦的全球通信。通过一个简化的代码验证了混合算法的正确性和并行实现的可行性.
英文摘要：
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.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
