Quantum Entanglement Assistance Improves the Capacity and Activates the Zero-Error Capacity of Classical Channels with Causal CSIT

2026-03-20

AI Summary

This work investigates whether quantum entanglement assistance can enhance the capacity of classical point-to-point channels and activate their zero-error capacity under causal channel state information at the transmitter (CSIT). By integrating information-theoretic principles, quantum entanglement resources, and a causal CSIT model, the study develops novel coding and transmission strategies. It establishes, for the first time, that under causal CSIT, quantum entanglement not only strictly increases the classical channel capacity but also activates a previously zero zero-error capacity to a positive value, thereby surpassing the fundamental limitations inherent in scenarios without CSIT.

Technology Category

• Reasoning under Uncertainty: Causality
• Machine Learning: Causal Learning
• Planning, Routing, and Scheduling: Scheduling under Uncertainty

Application Category

• Security and Privacy: Privacy-enhancing technologies
• Semantics and Knowledge: Methods to enhance, augment, integrate or synergize semantic models such as knowledge graphs and LLMs
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

For classical point-to-point channels, it has been shown by Bennett et al. that quantum entanglement assistance cannot improve their capacity, and by Cubitt et al. that entanglement assistance cannot activate (increase from zero to non-zero) their zero-error capacity. In contrast, we show that for classical point-to-point channels with causal CSIT (channel state information at the transmitter), quantum entanglement assistance can in some cases improve their capacity, and in some cases activate their zero-error capacity.

Problem

• quantum entanglement
• classical channels
• causal CSIT
• channel capacity
• zero-error capacity

Innovation

• quantum entanglement assistance
• causal CSIT
• classical channel capacity
• zero-error capacity
• channel state information