On a Nonlinear Newtonian Gravity and Charging a Black Hole
  A scalar field gravitational analog of the Reissner-Nordstrom solution is investigated. The nonlinear Newtonian model has an upper-limit of charge for a central mass which agrees with the general relativistic condition required for the existence of the black hole horizon. The maximum limit for accumulation by bombardment of charged particles is found. The aim is to investigate the resulting physics after severing the effects of curvature from the effects of energy-mass equivalence. 
Michael R.R. Good