THE LOW-ENERGY EFFECTIVE LAGRANGIAN FOR PHOTON INTERACTIONS IN ANY DIMENSION

The subject of low energy photon-photon scattering is considered in ar bitrary-dimensional space-time and the interaction is widened to inclu de scattering events involving an arbitrary number of photons. The eff ective interaction Lagrangian for these processes in QED has been dete rmined in a manifestly invariant form. This generalization resolves th e structure of the weak field Euler-Heisenberg Lagrangian and indicate s that the component invariant functions have coefficients related not only to the spacetime dimension but also to the coefficients of the B ernoulli polynomial.