Almost all pure entangled states enable unbounded nonlocality sharing

• URL: http://arxiv.org/abs/2607.24700v1
• Date: Mon, 27 Jul 2026 17:43:46 GMT
• Title: Almost all pure entangled states enable unbounded nonlocality sharing
• Abstract summary: We establish a connection between Hardy's paradox and nonlocality sharing in sequential bipartite scenarios.<n>We show that any correlations exhibiting a Hardy paradox in the two-input two-output scenario enable sequential violations of the CHSH inequality.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We establish a connection between Hardy's paradox and nonlocality sharing in sequential bipartite scenarios, where each subsystem is measured in turn by a chain of observers. We show that any correlations exhibiting a Hardy paradox in the two-input two-output scenario enable sequential violations of the CHSH inequality between arbitrarily many pairs of observers, using only projective measurements and the assistance of a small local ancilla system. Since almost all pure entangled states, with the only exception of the maximally entangled one, admit Hardy correlations, our protocol applies generically: almost all pure entangled states, if assisted by a local ancilla, allow for nonlocality sharing between arbitrarily many observer pairs using only projective measurements.

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