  There has recently been a strong revival of interest in quasi-extremal
magnetically charged black holes. In the asymptotically flat case, it is
possible to choose the magnetic charge of such an object in such a manner that
the black hole is surrounded by a corona in which electroweak symmetry is
restored on macroscopic scales, a result of very considerable interest. We
argue that holographic duality indicates that the asymptotically AdS analogues
of these black holes have several interesting properties: the dual theory is
only physical if the black hole is required to rotate; in the rotating case,
the magnetic field at the poles does not attain its maximum on the event
horizon, but rather somewhat outside it; the magnetic field at the equator is
not a monotonically decreasing function of the magnetic charge; the electric
fields induced by the rotation, while smaller than their magnetic counterparts,
are by no means negligible; the maximal electric field often occurs neither at
the poles nor at the equator; and so on. Most importantly, in the magnetically
charged case it is possible to avoid the superradiant instability to which
neutral AdS-Kerr black holes are subject; but the need to avoid this
instability imposes upper bounds on the magnetic and electric fields. In some
circumstances, therefore, the corona may not exist in the asymptotically AdS
case.
