Nonperturbative Pauli-Villars regularization of vacuum polarization in light-front QED

Understand

We continue the development of a nonperturbative light-front Hamiltonian method for the solution of quantum field theories by considering the one-photon eigenstate of Lorentz-gauge QED.

• The photon state is computed nonperturbatively for a Fock basis with a bare photon state and electron-positron pair states.
• The calculation is regulated by the inclusion of Pauli-Villars (PV) fermions, with one flavor to make the integrals finite and a second flavor to guarantee a zero mass for the physical photon eigenstate.
• We compute in detail the constraints on the PV coupling strengths that this zero mass implies.