  Neutral stellar core at or over nuclear densities is described by a positive
charged baryon core and negative charged electron fluid since they possess
different masses and interactions. Based on a simplified model of a
gravitationally collapsing or pulsating baryon core, we approximately integrate
the Einstein-Maxwell equations and the equations for the number and
energy-momentum conservation of complete degenerate electron fluid. We show
possible electric processes that lead to the production of electron-positron
pairs in the boundary of a baryon core and calculate the number and energy of
electron-positron pairs. This can be relevant for understanding the energetic
sources of supernovae and gamma-ray bursts.
