14.4: Lorenz Condition
- Page ID
- 32830
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It turns out that the four components of the potential four-momentum are not independent, but are subject to the condition
\[\frac{\partial Q_{x}}{\partial x}+\frac{\partial Q_{y}}{\partial y}+\frac{\partial Q_{z}}{\partial z}+\frac{1}{c^{2}} \frac{\partial U}{\partial t}=0 \label{14.16}\]
This is called the Lorenz condition. The physical meaning of this condition will become clear when we study electromagnetism.