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Szekeres · source-snapshot-bc3404156f6e
已登记出处中的最早位置:§9.4 · zh-CN。
来源短摘录与定位
§9.4 · zh-CN · translation · unreviewed
如同例 9.3 中那样,设闵可夫斯基时空中存在连续的电荷分布,其电荷密度为 ,电荷通量密度或电流密度为 ,其中 是流体的速度场。系统的总电荷是标量——否则未电离气体一般不会电中性。在流体于任一事件 处的局部瞬时静止系中,电荷密度记为 ,称为 固有电荷密度(proper charge density)。可以假定它是标量,因为它是相对于 处的特定惯性系定义的。另一方面,电荷密度 由下式给出
§9.4 · en · original_transcription · unreviewed
As in Example 9.3, let there be a continuous distribution of electric charge present in Minkowski space-time, having charge density and charge flux density or current density where is the velocity field of the fluid. The total charge of a system is a scalar quantity – else an unionized gase would not generally be electrically neutral. Charge density in a local instantaneous rest frame of the fluid at any event is denoted and is known as proper charge density. It may be assumed to be a scalar quantity, since it is defined in a specific inertial frame at . On the other hand, the charge density is given by