Sharp Contradiction for Local-Hidden-State Model in Quantum Steering

TL;DR

This paper introduces a GHZ-like contradiction for bipartite pure entangled states, establishing a new no-go theorem that rules out local hidden state models in quantum steering, thus deepening understanding of quantum nonlocality.

Contribution

It presents a simple, GHZ-like contradiction for bipartite states, providing a new no-go theorem for local hidden states in quantum steering.

Findings

Proves a no-go theorem for local hidden state models in bipartite entanglement.

Introduces a GHZ-like contradiction applicable to all bipartite pure entangled states.

Highlights the contradiction as the closest form to the original EPR paradox.

Abstract

In quantum theory, no-go theorems are important as they rule out the existence of a particular physical model under consideration. For instance, the Greenberger-Horne-Zeilinger (GHZ) theorem serves as a no-go theorem for the nonexistence of local hidden variable models by presenting a full contradiction for the multipartite GHZ states. However, the elegant GHZ argument for Bell's nonlocality does not go through for bipartite Einstein-Podolsky-Rosen (EPR) state. Recent study on quantum nonlocality has shown that the more precise description of EPR's original scenario is "steering", i.e., the nonexistence of local hidden state models. Here, we present a simple GHZ-like contradiction for any bipartite pure entangled state, thus proving a no-go theorem for the nonexistence of local hidden state models in the EPR paradox. This also indicates that the very simple steering paradox presented here is indeed the closest form to the original spirit of the EPR paradox.