Violating the no-signaling principle with classical inseparable beams in an optical parity-time symmetric system

TL;DR

This paper demonstrates that classical inseparable beams in a parity-time symmetric optical system can violate the no-signaling principle, revealing that such paradoxes are not exclusive to quantum mechanics but also occur classically.

Contribution

It shows classical optical systems with PT symmetry can violate no-signaling, bridging classical and quantum paradoxes and enabling experimental exploration of PT symmetry.

Findings

Classical inseparable beams can violate no-signaling in PT-symmetric systems.

Violations are analogous to quantum no-signaling issues.

Classical systems can simulate quantum paradoxes.

Abstract

We show that the no-signaling principle can be violated with classical inseparable beams in the presence of a parity-time (PT) symmetric subsystem. Thus, the problems associated to PT-symmetric quantum theories recently discovered by Lee et al. [Phys. Rev. Lett. 112, 130404 (2014)] are not exclusive to quantum mechanics, but already exist in the classical case. The possibility to implement local optical PT-symmetric subsystems via light-matter interactions enables the experimental exploration of local PT symmetry and subtle quantum concepts via classical analogues.