Bose-Einstein condensates and quantum non-locality

TL;DR

This paper explores the EPR argument in the context of macroscopic Bose-Einstein condensates, suggesting that quantum non-locality may be observable at larger scales where Bohr's traditional refutation does not apply.

Contribution

It extends the EPR argument to macroscopic systems like Bose-Einstein condensates, challenging Bohr's dismissal of local hidden variables at larger scales.

Findings

EPR argument can be applied to macroscopic quantum states

Bohr's refutation may not hold for macroscopic systems

Potential for observing quantum non-locality in BECs

Abstract

The EPR argument points to the existence of additional variables that are necessary to complete standard quantum theory. It was dismissed by Bohr because it attributes physical reality to isolated microscopic systems, independently of the macroscopic measurement apparatus. Here, we transpose the EPR argument to macroscopic systems, assuming that they are in spatially extended Fock spin states and subject to spin measurements in remote regions of space. Bohr's refutation of the EPR argument does not seem to apply in this case, since the difference of scale between the microscopic measured system and the macroscopic measuring apparatus can no longer be invoked.