ER=EPR, GHZ, and the consistency of quantum measurements
This paper illustrates various aspects of the ER=EPR conjecture. It begins with a brief heuristic argument, using the Ryu‐Takayanagi correspondence, for why entanglement between black holes implies the existence of Einstein‐Rosen bridges. The main part of the paper addresses a fundamental question: Is ER=EPR consistent with the standard postulates of quantum mechanics? Naively it seems to lead to an inconsistency between observations made on entangled systems by different observers. The resolution of the paradox lies in the properties of multiple black holes, entangled in the Greenberger‐Horne‐Zeilinger pattern. The last part of the paper is about entanglement as a resource for quantum communication. ER=EPR provides a way to visualize protocols like quantum teleportation. In some sense teleportation takes place through the wormhole, but as usual, classical communication is necessary to complete the protocol.