在使用引力系统的大规模模拟中测试近似值
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在PubMed上查看摘要
概括
此摘要是机器生成的。星系模拟中的粒子网近似破坏了动量保存,影响了星系的稳定性. 将重力修改为反向吸引力,就像在f (R) 相对论中一样,可以确保矮星系的稳定性.
科学领域
- 天体物理学
- 计算宇宙学
- 引力物理
背景情况
- 粒子网 (PM) 近似,包括粒子网 (P3M) 和树PM,对于大规模结构和星系模拟至关重要.
- 这些方法使用基于网格的计算来估计远程力,这可能会破坏相互作用对称性并违反保存规律.
研究的目的
- 研究粒子网近似对银河系动力学和稳定性的影响.
- 为了比较带有和没有PM近似的原力模拟结果.
主要方法
- 对一个小矮星系 (≈500个粒子) 进行了直接的原力N体模拟.
- 进行了带有和没有粒子网近似的模拟,以隔离它们的影响.
- 在两种模拟类型中检查了动量和角动量的保存.
主要成果
- 发现粒子网近似是敏感的,
- 模拟表明近似可以导致粒子从绑定旋转中释放出来.
- 精确的模拟,虽然仅限于小型系统,但却揭示了这些稳定性问题.
结论
- 粒子网近似引入星系模拟中的不稳定性,影响长期动态.
- 修改重力从反正方律到反向吸引力,与f ((R)) 修改重力一致,可以恢复矮星系的稳定性.
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