Editing Proca action (section)

==Gauge fixing==

The Proca action is the [[gauge fixing|gauge-fixed]] version of the [[Stueckelberg action]] via the [[Higgs mechanism]]. Quantizing the Proca action requires the use of [[second class constraints]].

If <math>\ m \neq 0\ ,</math> they are not invariant under the gauge transformations of electromagnetism

:<math>\ B^\mu \mapsto B^\mu - \partial^\mu f\ </math>

where <math>\ f\ </math> is an arbitrary function.