Magic words encode mathematical routines and/or thought processes so common in the field of study that no one wishes to redo. Magic words speed up communication between experts but often utterly confuse learners.

1. The matter field \(\phi\) has charge \(q\) under \(U(1)\) symmetry
   translation: \(\phi\) transforms as \(\phi\rightarrow e^{iq\alpha}\phi\) for a \(U(1)\) symmetry parametrized by \(\alpha\).
2. Gauge this action
   translation: Replace \(\partial_\mu\) with \(\partial_\mu – Q(A_\mu+B_\mu+\dots)\), where \(A_\mu,B_\mu,\dots\) are gauge fields, one for each matter field whose derivative shows up in the theory. The charge operator \(Q\) binds each field to its appropriate charge.