Toward the Observation of Entangled Pairs in BEC analogue Expanding Universes

TL;DR

This paper investigates the potential to observe quantum entanglement resulting from pair creation in Bose-Einstein Condensate analogues of expanding universes, assessing experimental feasibility and optimal conditions for detection.

Contribution

It quantifies entanglement in BEC analogues of expanding universes and evaluates experimental conditions needed for its observation, advancing understanding of quantum effects in curved spacetime analogues.

Findings

Entanglement can be detected at ~2σ significance with current setups.

Modest improvements can increase significance to >3.3σ.

Experimental configurations can be optimized to observe quantum pair creation evidence.

Abstract

Pair creation is a fundamental prediction of quantum field theory in curved spacetimes. While classical aspects of this phenomenon have been observed, the experimental confirmation of its quantum origin remains elusive. In this article, we quantify the entanglement produced by pair creation in two dimensional Bose-Einstein Condensate (BEC) analogues of expanding universes and examine the impact of various experimental factors, including decoherence from thermal noise and losses. Our analysis evaluates the feasibility of detecting entanglement in these systems and identifies optimal experimental configurations for achieving this goal. Focusing on the experimental setup detailed in \cite{Viermann:2022wgw}, we demonstrate that entanglement can be observed in these BEC analogues at a significance level of $\sim 2\sigma$ with current capabilities, and at $\gtrsim 3.3\sigma$ with modest improvements. Achieving this would provide unequivocal evidence of the quantum nature of pair creation and validate one of the most iconic predictions of quantum field theory in curved spacetimes.