Context:
For a third objection to firewalls I shall assume that if firewalls form around black holes in asymptotically flat space, then they should also form around black holes in asymptotically anti deSitter space for very
small lambda. One would expect that quantum gravity should be CPT invariant. Condsider a gedanden experiment in which Lorentzian asymptotically anti deSitter space has matter fields excieted in certain modes.
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http://arxiv.org/pdf/1401.5761v1.pdf