Maxwell equations

From DispersiveWiki

(Redirected from Maxwell equation)
Jump to: navigation, search

The Maxwell equations are the special case of the Yang-Mills equations when the gauge group is just the abelian circle group U(1). These equations take the form

\partial^\alpha F_{\alpha \beta} = 0

where F is the curvature of a U(1) connection A_\alpha: R^{1+d} \to R:

F_{\alpha \beta} := \partial_\alpha A_\beta - \partial_\beta A_\alpha.

Note that the Bianchi identity also gives the equation

\partial_\gamma F_{\alpha \beta} + \partial_\alpha F_{\beta \gamma} + \partial_\gamma F_{\beta \alpha} = 0

which is also traditionally given as one of the Maxwell equations.

In the presence of a current jβ, the Maxwell equations now take the form

\partial^\alpha F_{\alpha \beta} = j_\beta

(after normalizing various physical constants).

The Maxwell equations are linear. However, by coupling the Maxwell equations to a scalar field one obtains the nonlinear Maxwell-Klein-Gordon equations.

Personal tools