A kind of model of quantum electrodynamics with nonlocal interaction

We present a kind of model of quantum electrodynamics with nonlocal interaction, all the action and the equations of motion of charged particle and electromagnetic field are given. The main characteristics of the theory are: the model obeys the action principle; free charged particle and free electromagnetic field obey the Dirac equation and the Maxwell equation of free fields, respectively; for the case of interaction, both the equations of motion of charged particle and electromagnetic field lead to the normal current conservation naturally; the theory is Lorentz invariant and gauge invariant, and returns to the conventional local QED under appropriate limit conditions. Taking advantage of the Yang-Feldman equations and the Lehmann-Symanzik- Zimmermann formalism, we establish the corresponding quantum theory.