In the Dirac equation for a massless fermion, for example, in the Weyl representation, we can split the equation into two separate equations for left-handed and right-handed electrons. In the Weyl represenation, the spinor is split as $\psi=(\psi_L,\psi_R)$
For the Maxwell equation for a massless photon, can we split this into two equations, for each of the two polarizations of light? I'm not sure how one would split the 4-vector potential $A_\mu$ into the two polarization states e.g. $\phi_L$ and $\phi_R$.
Also, is there some operator analagous to the $\frac{1}{2}(1+\gamma^5)$ operator for the Dirac equation that gives us one of the two polarization states?