Multipartite nonlocality in the presence of particle-number super-selection rules

TL;DR

This paper investigates how super-selection rules impact the detection of multipartite nonlocality, revealing limitations on observing genuine multipartite nonlocality when particle numbers are insufficient, with practical experimental implications.

Contribution

It demonstrates that super-selection rules restrict genuine multipartite nonlocality detection in multipartite states with fewer particles than parties.

Findings

Super-selection rules limit genuinely multipartite nonlocality detection.

Non-genuinely multipartite nonlocality remains unaffected by super-selection rules.

Experimental tests proposed are feasible with current techniques.

Abstract

Super-selection rules severely restrict the possible operations one can perform on an entangled state. Their effect on the observation of non-locality through the Bell inequalities is only partially understood in the bipartite case. In this article we examine a range of multipartite entangled states and find that for those states the super-selection rules limit the genuinely multipartite nonlocality but not the non-genuinely multipartite. We argue that when the number of particles is smaller than the number of parties, genuinely multipartite nonlocality cannot be detected unless the super-selection rules can be relaxed. The tests proposed in the paper can be implemented using routinely used experimental techniques.