Discreteness Noise versus Force Errors in N-Body Simulations: Erratum
Discreteness Noise versus Force Errors in N-Body Simulations: Erratum
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N 体模拟中的离散噪声与力误差：勘误表
DOI：
10.1086/186910
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Makino
中科院分区：
文献类型：
--
作者：
L. Hernquist;P. Hut;J. Makino
研究了力计算的数值误差对无碰撞N体模拟结果精度的影响。我们的主要结果是，力的计算精度低-百分之几的每个粒子对-是足够的，无论粒子的数量。更高的精度是无用的，因为离散噪声，即，两体弛豫效应主导误差。我们已经进行了数值实验两种不同的情况下：一个专用机器与低精度的硬件和树代码。在这两种情况下，两体松弛效应主导的误差和力计算中的误差的影响几乎可以忽略不计的所有情况下，我们尝试。
We have investigated the effect of the numerical error of the force calculation on the accuracy of the result of collisionless N-body simulations. Our main result is that force calculation with a low accuracy — a few percent for each particle pair — is sufficient, irrespective of the number of particles. Higher accuracy is useless since the discreteness noise, i.e., the two-body relaxation effect, dominates the error. We have performed numerical experiments for two different cases: a special-purpose machine with low-precision hardware and the tree-code. In both cases, the two-body relaxation effect dominates the error and the effect of the error in the force calculation is practically negligible for all cases we tried.