论文标题
带电颗粒的经典散射中渐近电磁场的角动量
Angular momentum of the asymptotic electromagnetic field in the classical scattering of charged particles
论文作者
论文摘要
我们在较晚的考奇表面上计算电磁场的角动量，其任意常数正常矢量与带电颗粒的经典散射相关。我们发现对角动量的时间独立贡献。这表明每个带电的粒子散射事件都伴随着电磁场的角动量的净移位。我们推测，这种转移与超级电磁记忆效应有关。我们认为，这种渐近角动量应包括在包含红外差异的量子理论中的渐近状态描述中。我们证明，只有在引用Cauchy Slice的正常载体时，才能显示出渐近电磁角动量的Lorentz协方差。
We compute the angular momentum of the electromagnetic field on a late time Cauchy surface with an arbitrary constant normal vector relevant for the classical scattering of charged particles. We find a time independent contribution to the angular momentum. This demonstrates that every charged particle scattering event is accompanied by a net shift in the angular momentum of the electromagnetic field. We speculate that this shift is related to a subleading electromagnetic memory effect. We argue that this asymptotic angular momentum should be included in the description of the asymptotic states in quantum theories containing infrared divergences. We demonstrate that the Lorentz covariance of the asymptotic electromagnetic angular momentum can only be exhibited upon making reference to the Cauchy slice's normal vector.
