The expectation value of electrical charge in charged vacuum is calculated utilizing the Thomas-Fermi model. We find almost complete screening of the nuclear charge. For any given nuclear density there is an upper bound for the electrical potential. For normal nuclear densities this value is - 250 MeV. This suggests that the vacuum is stable against spontaneous formation of heavy, charged particles.

• Received 2 December 1974

DOI:https://doi.org/10.1103/PhysRevLett.34.349