If it is even assumed virtual photons can be exchanged between a
charge within a black hole and another charge absorbed within (or
arbitrarily close to) the singularity, and we examine the force
balance between the Coulomb force:
Fc = K q^2 / r
and gravitational force:
Fg = G m_e M / r
we see that the gravitational force matches the Coulomb force at all
r when:
M = K q^2 / (G m_e) = 3.7956x10^12 kg
and given the mass of the sun is 1.9891x10^30 kg, any black hole
with mass 1.91x10^-18 the mass of the sun can clearly produce pair
separation. If any significantly sized black hole center is a
singularity then the volume of space around it within some critial
radius R a function of mass will have sufficient field strength and
field gradient to accomplish pair separation.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/