In differential form: \[ \begin{aligned} \nabla\cdot\textbf{E} &= {\rho \over \varepsilon_0}\\ \nabla\cdot\textbf{B} &= 0\\ \nabla\times\textbf{E} &= -\frac{\partial\textbf{B}}{\partial t}\\ \nabla\times\textbf{B}&=\mu_0\left(\textbf{J} + \varepsilon_0\frac{\partial\textbf{E}}{\partial t}\right) \end{aligned} \]