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Authors
Juan Maldacena
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We discuss aspects of magnetically charged black holes in the Standard Model. For a range of charges, we argue that the electroweak symmetry is restored in the near horizon region. The extent of this phase can be macroscopic. If $Q$ is the integer magnetic charge, the fermions lead to order $Q$ massless two dimensional fermions moving along the magnetic field lines. These greatly enhance Hawking radiation effects.
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In five-dimensional minimal supergravity, there are spherical black holes with nontrivial topology outside the horizon which have the same conserved charges at infinity as the BMPV solution. We show that some of these black holes have greater entropy than the BMPV solution. These spacetimes are all asymptotically flat, stationary, and supersymmetric. We also show that there is a limit in which the black hole shrinks to zero size and the solution becomes a nonsingular bubbling geometry. Thus, these solutions provide explicit analytic examples of placing black holes inside solitons.
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