Causal Structure and the Delicacy of Holographic Arguments for Unitarity

I draw out a hidden assumption of the argument, that the causal structure of the interior must be nice in a particular way. I conclude that his argument thereby either begs the question or else necessitates a peculiarly strong and promiscuous global non-locality of spacetime structure, which I find hard to accept.
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Speaker: Erik Curiel (Munich Center for Mathematical Philosophy, LMU Munich)