Quantum entanglement in the multiverse

TL;DR

This paper demonstrates that the quantum state of a multiverse composed of disconnected regions can be described as a squeezed state, enabling analysis of quantum correlations, violations of classical inequalities, and thermodynamical properties of entanglement.

Contribution

It introduces a model where the multiverse's quantum state is a squeezed state, providing new insights into quantum correlations and entanglement in cosmological multiverse scenarios.

Findings

Quantum states of the multiverse are squeezed states.

Entanglement thermodynamics between universes is analyzed.

Energy of entanglement between universe modes is computed.

Abstract

In this paper it is shown that the quantum state of a multiverse made up of classically disconnected regions of the space-time, whose dynamical evolution is dominated by a homogeneous and isotropic fluid, is given by a squeezed state. These are typical quantum states that have no classical counterpart and, therefore, they allow us to analyze the violation of classical inequalities as well as the EPR argument in the context of the quantum multiverse. The thermodynamical properties of entanglement are calculated for a composite quantum state of two universes whose states are quantum mechanically correlated. The energy of entanglement between the positive and negative modes of a scalar field, which correspond to the expanding and contracting branches of a phantom universe, respectively, are also computed.