In our Comment we question the validity of the claim made by Campos and Cabrera [Phys. Rev. Res. 2, 013051 (2020)] that their solutions of the Dirac equation in an external time-dependent electromagnetic field describe beams of electrons. In every time-dependent field, no matter how weak, which has an infinite time duration, there is continuous electron-positron pair creation and annihilation. Without the proper accounting for these processes, the mathematical solutions of the Dirac equation are not directly applicable to realistic physical situations. In particular, the time evolution of the average values $\langle x\rangle$ and $\langle y\rangle$ does not describe the electron trajectory but the motion of some combination of the electron and positron charge distributions with pathological properties (zitterbewegung).

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评论“狄拉克方程的非弥散解析解”

在我们的评论中，我们质疑Campos和Cabrera提出的主张的有效性。牧师 2，013051（2020）]，它们在外部狄拉克方程的解依赖于时间的电磁场描述的电子束。在每一个与时间相关的领域，无论多么薄弱，具有无限的持续时间，有连续的电子-正电子对产生和湮灭。如果没有适当考虑这些过程，狄拉克方程的数学解就不能直接应用于现实的物理情况。特别是平均值的时间演变$〈X〉$ 和 $〈ÿ〉$并未描述电子轨迹，而是描述了具有病理性质的电子和正电子电荷分布的某种组合的运动（zitterbewegung）。