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arXiv · 2203.05387

A New Guest in the Third Quantized Multiverse

Samuel Barroso Bellido·Fabian Wagner
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Abstract

In the present article we point out a conceptual issue of the Third Quantization formalism for Canonical Quantum Gravity. Based on earlier results on interuniversal entanglement, the picture of noninteracting universe-antiuniverse pairs is incomplete. In particular, the variation of the entanglement entropy with the scale factor, understood as a measure of time, implies either an interaction between pairs of universes or universes with a heat bath, i.e. an external field. We propose a simple solution to the problem by adding a new quantum field to the formalism. Correspondingly, particles of this field mediate interactions between universes -- depending on the model at tree level or one loop -- and may further provide a heat bath in the background.

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Samuel Barroso Bellido, Fabian Wagner. 2022-03-10. A New Guest in the Third Quantized Multiverse. https://doi.org/10.1103/physrevd.105.106001

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