Vacuum polarization in a strong external field

Vacuum polarization in the field of a high-Z finite-size nucleus is examined, and the polarization charge density in coordinate space of order alpha(Z alpha)exp n not less than 3 is calculated.

Abstract

Vacuum polarization in the field of a high-Z finite-size nucleus is examined, and the polarization charge density in coordinate space of order \ensuremath{\alpha}(Z\ensuremath{\alpha}${)}^{n}$ with n\ensuremath{\ge}3 is calculated. Energy-level shifts of K- and L-shell electrons in hydrogenlike systems are given.