# Lorentz gauge

QuasarBoy543298
hi, I'm currently taking a classical field theory class (electromagnetism in the language of tensors and actions and etc) and we have just encountered the gauge symmetry, that is for the 4 vector potential we can add a gradient of some smooth function and get the same physics (if we take Aμ → Aμ + ∂μf the actions stays the same, except some irrelevant constant).
now after that long preview, my question is - how can we conclude from that freedom that we can find a solution for the field A, with any boundary conditions, that satisfies the Lorentz gauge ( ∂μAμ = 0)?

Cryo

Homework Helper
Gold Member
That is done on most textbooks. It is the Lorenz gauge.

vanhees71