- #1
jtceleron
- 16
- 0
This question is from K. Huang, Quantum Field Theory: from operators to path integrals.
He says that, under a continuous infinitesimal transformation,
\phi(x)->\phi(x)+\delta\phi
the change of the Lagrangian density must be in the from
\deltaL=∂^{\mu}W_{\mu}(x)
It is easily understood that this quantity must be Lorentz-invariant, but why should only be this form, not others (e.g. without derivatives).
He says that, under a continuous infinitesimal transformation,
\phi(x)->\phi(x)+\delta\phi
the change of the Lagrangian density must be in the from
\deltaL=∂^{\mu}W_{\mu}(x)
It is easily understood that this quantity must be Lorentz-invariant, but why should only be this form, not others (e.g. without derivatives).
