一种场理论方法,用于模拟散流相对论流体
Nils Andersson1, Thomas Celora2, Gregory Comer3
1Mathematical Sciences and STAG Research Centre, University of Southampton, Southampton SO17 1BJ, UK.
Entropy (Basel, Switzerland)
|August 29, 2024
概括
我们为具有散射的相对论流体开发了一种作用原理,其中包含粒子和成分. 这种方法自然产生粘度系数,与传统方法不同.
科学领域:
- 物理 物理学 物理
- 一般相对论一般相对论.
- 流体动力学 流体动力学
背景情况:
- 相对论流体中的分散现象对于天体物理学和宇宙学模型至关重要.
- 现有的模型通常依赖于现象学描述或对运输系数的外部处方.
研究的目的:
- 在广义相对论中,为单流体,两构成系统 (粒子和) 制定第一原理的作用原理.
- 从这个原理中推导出运动方程,产量和能量-动量-应力张量.
- 调查散散系数的起源和性质,如散体和剪切粘度.
主要方法:
- 拉格朗的构造结合了一个新的术语:物质空间尺度的适当时间导数.
- 场方程的导出,生成率和能量-动量-应力张量.
- 结果与Onsager相互关系方法和相对论纳维埃-斯托克斯方程进行比较.
主要成果:
- 作用原理自然产生与散装和剪切粘度相关的术语.
- 从动作原理衍生的模型产生了与相对论纳维埃-斯托克斯方程相同的生成率.
- 与基于Onsager的模型不同,粘度系数本质上来自拉格朗的方程,并满足进化方程.
结论:
- 开发的作用原理为描述散射相对论流体提供了一个一致的框架.
- 这种方法提供了更深入的,第一原则的这种系统的粘度的理解.
- 运输系数的内在导出建议在广义相对论中对流体动力学进行更基本的描述.
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