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arXiv · 2507.10830

Facets of Non-locality and Advantage in Entanglement-Assisted Classical Communication Tasks

Sumit Rout·Anubhav Chaturvedi·Some Sankar Bhattacharya·Paweł Horodecki
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Abstract

We reveal key connections between non-locality and advantage in correlation-assisted classical communication. First, using the wire-cutting technique, we provide a Bell inequality tailored to any correlation-assisted bounded classical communication task. The violation of this inequality by a quantum correlation is equivalent to its quantum-assisted advantage in the corresponding communication task. Next, we introduce wire-reading, which leverages the readability of classical messages to demonstrate advantageous assistance of non-local correlations in setups where no such advantage can be otherwise observed. Building on this, we introduce families of classical communication tasks in a Bob-without-input prepare-and-measure scenario, where non-local correlation enhances bounded classical communication while shared randomness assistance yields strictly suboptimal payoff. For the first family of tasks, assistance from any non-local facet leads to optimal payoff, while each task in the second family is tailored to a non-local facet. We reveal quantum advantage in these tasks, including qutrit over qubit entanglement advantage.

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Sumit Rout, Anubhav Chaturvedi, Some Sankar Bhattacharya, Paweł Horodecki. 2025-07-14. Facets of Non-locality and Advantage in Entanglement-Assisted Classical Communication Tasks. https://arxiv.org/abs/2507.10830

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