标题： 不变的相对论运动学：相空间三角剖分 显示英文标题

标题： Invariant relativistic kinematics: Phase space triangulation

摘要： 粒子衰变宽度和散射截面的计算自然分解为一个量子力学振幅和一个相对论相空间（PS）。 这个PS可以用平行多面体来表述，从而提供框架无关的不变量。 我们展示这些不变量如何与框架相关的可观测量（如粒子的动量、能量以及它们之间的角度）相关联。 此外，我们推导了具有简单积分限的n维PS的表达式，这些表达式特别适合解析处理。 为此，我们发展了一种图形描述方法，使用PS图来允许直观地识别任意n维情况下的最优积分变量集。 显示英文摘要

摘要： The calculation of particle decay widths and scattering cross sections naturally decomposes into a quantum mechanical amplitude and a relativistic phase space (PS). This PS can be formulated in terms of parallelotopes providing frame independent invariants. We demonstrate how these invariants are related to frame dependent observables such as momenta, energies, and angles between particles. Furthermore, we derive expressions for n-dimensional PSs featuring simple integration limits that are particularly well suited for an analytical treatment. To that end we develop a pictorial description using PS diagrams that allow to straightforwardly identify the optimal set of integration variables for arbitrary n.