The implicit midpoint method described by Chambliss and Franklin [Am. J. Phys. 88, 1075 (2020)] is known not to exactly conserve energy for a spatially varying magnetic field, nor does it conserve angular momentum in a constant magnetic field. It is, therefore, not competitive with the widely used Boris solver in plasma physics, which conserves both.

中文翻译：

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评论“一种磁速度 Verlet 方法” [Am. J. Phys.88, 1075 (2020)]

Chambliss 和 Franklin [Am. J.物理。88 , 1075 (2020)] 已知不会为空间变化的磁场精确守恒能量，也不会在恒定磁场中守恒角动量。因此，它无法与等离子体物理学中广泛使用的 Boris 求解器竞争，后者同时保存了两者。