仅仅分散关系不能保证因果关系
L Gavassino1, M Disconzi1, J Noronha2
1Department of Mathematics, Vanderbilt University, 1326 Stevenson Center Lane, Nashville, Tennessee 37240, USA.
Physical review letters
|May 3, 2024
概括
分散介质中的因果关系并不能由个别的分散关系来保证. 真正的因果关系来自稳定的物理模型中所有激发分支的叠加,类似于量子力学的反粒子.
科学领域:
- 物理 物理学 物理
- 波浪传播 波浪传播
- 相对论理论相对论的理论
背景情况:
- 分散关系 (ω(k)) 描述了介质中的波传播.
- 确保因果关系 (光内的传播) 在物理学中至关重要.
研究的目的:
- 研究平面波的线性叠加在哪些条件下因果传播.
- 确定分散关系在确定因果关系中的作用.
- 在物理模型中探索因果关系的出现.
主要方法:
- 分析平面波的线性叠加,具有单值,共变量稳定的分散关系.
- 对光下传播的数学条件的检查.
- 调查由所有激发分支叠加而产生的因果关系.
主要成果:
- 线性叠加在光外传播,除非 ω(k) = a+bk.
- 没有单一的分散关系可以保证光下传播.
- 因果关系来自叠加激发分支中的取消.
结论:
- 因果关系不是个别分散关系的内在属性.
- 因果关系源于稳定理论中所有激发分支的集体行为.
- 相对论流体力学中的非水力动力学模式与反粒子类似.
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