AB效应与Aharonov-Susskind电荷非超选择
AB effect and Aharonov-Susskind charge non-superselection
摘要：
我们考虑一个粒子在一个磁通量附近运动的相干叠加态与不同的电荷。形式上，它应该获得一个（规范依赖）AB相对相位之间的电荷状态，即使是一个不完整的循环。如果是可测量的，这种几何的而不是拓扑的AB相似乎会破坏规范不变性。Wick、Wightman和Wigner认为，由于（全局）电荷相关相变在物理上是不可观测的，因此电荷态叠加也是非物理的（“电荷超选择规则”）。这将以一种微不足道的方式解决这个明显的悖论。然而，Aharonov和Susskind对这个超选择规则提出了异议：他们区分了这种依赖于全局电荷的变换和两个粒子的相对电荷间相位的变换，并表明后者\emph{could}原则上是可观察的！最后，一旦我们考虑Aharonov-Susskind相位检测器测量的相位的“校准”以及粒子在其初始点的相位，悖论再次消失。事实证明，这样的检测器只能区分两个路径的相对相位，如果他们的（定向）差异形成一个环周围的通量。
英文摘要：
We consider a particle in a coherent superposition of states with different electric charge moving in the vicinity of a magnetic flux. Formally, it should acquire a (gauge-dependent) AB relative phase between the charge states, even for an incomplete loop. If measureable, such a geometric, rather than topological, AB-phase would seem to break gauge invariance. Wick, Wightman and Wigner argued that since (global) charge-dependent phase transformations are physically unobservable, charge state superpositions are unphysical (`charge superselection rule'). This would resolve the apparent paradox in a trivial way. However, Aharonov and Susskind disputed this superselection rule: they distinguished between such global charge-dependent transformations, and transformations of the relative inter-charge phases of two particles, and showed that the latter \emph{could} in principle be observable! Finally, the paradox again disappears once we considers the `calibration' of the phase measured by the Aharonov-Susskind phase detectors, as well as the phase of the particle at its initial point. It turns out that such a detector can only distinguish between the relative phases of two paths if their (oriented) difference forms a loop around the flux.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
