High-Energy Delbrück Scattering from Nuclei

We study the elastic scattering of a high-energy photon from a heavy nucleus, considered to be a static Coulomb field due to the charge $Z_e$. Exchange of an arbitrarily large number of photons with the nucleus is taken into account, and the effect of this multiphoton exchange is found to be very large, particularly for momentum transfers which are large compared with the rest mass of the electron. In addition, an interesting theoretical problem in this connection is formulated but unfortunately not solved.