Zaslavskii has suggested how to tighten Bekenstein's bound on entropy when
the object is electrically charged. Recently Hod has provided a second tighter
version of the bound applicable when the object is rotating. Here we derive
Zaslavskii's optimized bound by considering the accretion of an ordinary
charged object by a black hole. The force originating from the polarization of
the black hole by a nearby charge is central to the derivation of the bound
from the generalized second law. We also conjecture an entropy bound for
charged rotating objects, a synthesis of Zaslavskii's and Hod's. On the basis
of the no hair principle for black holes, we show that this last bound cannot
be tightened further in a generic way by knowledge of ``global'' conserved
charges, e.g., baryon number, which may be borne by the object.Comment: 21 pages, RevTex, Regularization of potential made clearer. Error in
energy of the particle corrected with no consequence for final conclusions.
New references adde
