Raychaudhuri's equation and aspects of relativistic charged collapse
  We use the Raychaudhuri equation to probe certain aspects related to the
gravitational collapse of a charged medium. The aim is to identify the stresses
the Maxwell field exerts on the fluid and discuss their potential implications.
Particular attention is given to those stresses that resist contraction. After
looking at the general case, we consider the two opposite limits of poor and
high electrical conductivity. In the former there are electric fields but no
currents, while in the latter the situation is reversed. When the conductivity
is low, we find that the main agents acting against the collapse are the
Coulomb forces triggered by the presence of an excess charge. At the ideal
Magnetohydrodynamic (MHD) limit, on the other hand, the strongest resistance
seems to come from the tension of the magnetic forcelines. In either case, we
discuss whether and how the aforementioned resisting stresses may halt the
contraction and provide a set of conditions making this likely to happen.
