# Dictionary:Hertz vector potential

A vector potential ${\displaystyle \Pi }$ from which both the EM vector potential A and the scalar potential ${\displaystyle \phi }$ can be derived by differentiation:
${\displaystyle {\textbf {A}}=\mu \varepsilon {\frac {\partial \Pi }{\partial t}}+\mu \sigma \Pi }$
${\displaystyle \phi =-\nabla \cdot \Pi }$.