  We show that, in a gravitational theory [in any number of dimensions greater
than 3] which admits BPS branes and AdS-Reissner-Nordstrom black holes with
flat event horizons, the specific [dimensionless] temperature of such a black
hole is bounded below by approximately 0.156875. This confirms the recent
suggestion by Hartnoll and Tavanfar, to the effect that no such black hole can
be arbitrarily cold, since from the AdS/CFT dual point of view the
low-temperature degrees of freedom should not be concealed by the equivalent of
an event horizon.
