Numeric simulation of relativistic stellar core collapse and the   formation of Reissner-Nordstrom space-times
  The time evolution of a set of 22 Mo unstable charged stars that collapse is computed integrating the Einstein-Maxwell equations. The model simulate the collapse of an spherical star that had exhausted its nuclear fuel and have or acquires a net electric charge in its core while collapsing. When the charge to mass ratio is Q/M >= 1 the star do not collapse and spreads. On the other hand, it is observed a different physical behavior with a charge to mass ratio 1 > Q/ M > 0.1. In this case, the collapsing matter forms a bubble enclosing a lower density core. We discuss an immediate astrophysical consequence of these results that is a more efficient neutrino trapping during the stellar collapse and an alternative mechanism for powerful supernova explosions. The outer space-time of the star is the Reissner-Nordstrom solution that match smoothly with our interior numerical solution, thus the collapsing models forms Reissner-Nordstrom black holes. 
Cristian R. Ghezzi and Patricio S. Letelier