Simulating equatorial measurements on GHZ states with finite expected communication cost

TL;DR

This paper presents a protocol to simulate equatorial measurements on multipartite GHZ states with a finite average communication cost, advancing understanding of quantum non-locality in complex systems.

Contribution

It introduces a novel protocol for simulating equatorial measurements on n-partite GHZ states with quadratic communication complexity, filling a gap in multipartite quantum simulation methods.

Findings

Simulation protocol uses O(n^2) bits of communication on average

Achieves accurate simulation of equatorial measurements on GHZ states

Advances understanding of quantum non-locality in multipartite systems

Abstract

The communication cost of simulating probability distributions obtained by measuring quantum states is a natural way to quantify quantum non-locality. While much is known in the case of bipartite entanglement, little has been done in the multipartite setting. In this paper, we focus on the GHZ state. Specifically, equatorial measurements lead to correlations similar to the ones obtained with Bell states. We give a protocol to simulate these measurements on the n-partite GHZ state using O(n^2) bits of communication on average.