论文标题
旋转张量和伪高格：从核冲突到引力物理
Spin tensor and pseudo-gauges: from nuclear collisions to gravitational physics
论文作者
论文摘要
旋转的相对论治疗是具有旧历史的基本主题。在各种物理环境中，有必要将相对论的总角动量分为轨道和旋转贡献。但是，这种分解受歧义的影响，因为人们总是可以重新定义轨道和旋转部分，并通过所谓的伪规变化。我们通过讨论能量摩托车和自旋张量的最常见选择，重点是它们的物理含义，并研究自旋矢量，这是一个伪估计不变的操作员，从而详细分析了这个问题。我们回顾角动量分解是对相对论自旋流体动力学和量子动力学理论的制定的关键成分，重点是相对论核碰撞，在这些核碰撞中，旋转物理学最近引起了极大的关注。此外，我们指出了伪规变化与质量相对论中心的不同定义之间的联系。最后，我们考虑了爱因斯坦 - 卡丹理论，这是传统的一般相对性的扩展，该理论可以自然定义自旋张量。
The relativistic treatment of spin is a fundamental subject which has an old history. In various physical contexts it is necessary to separate the relativistic total angular momentum into an orbital and spin contribution. However, such decomposition is affected by ambiguities since one can always redefine the orbital and spin part through the so-called pseudo-gauge transformations. We analyze this problem in detail by discussing the most common choices of energy-momentum and spin tensors with an emphasis on their physical implications, and study the spin vector which is a pseudo-gauge invariant operator. We review the angular momentum decomposition as a crucial ingredient for the formulation of relativistic spin hydrodynamics and quantum kinetic theory with a focus on relativistic nuclear collisions, where spin physics has recently attracted significant attention. Furthermore, we point out the connection between pseudo-gauge transformations and the different definitions of the relativistic center of mass. Finally, we consider the Einstein-Cartan theory, an extension of conventional general relativity, which allows for a natural definition of the spin tensor.
