Renormalization constant
= Renormalization constant
{title2=$Z$}
A <renormalization constant> relates bare parameters or fields to renormalized ones, for example $\phi_0=Z_\phi^{1/2}\phi$. Its regulator-dependent terms cancel <ultraviolet divergences>; its finite part depends on the <renormalization scheme>. Field and vertex constants may depend on the chosen <gauge fixing> even when physical observables do not.