Enhancing Sum Capacity via Quantum and No-Signaling Cooperation Between Transmitters

2025-09-09

AI Summary

This work addresses the open question of whether classical, quantum, or no-signaling cooperation can strictly increase the sum capacity of discrete memoryless interference channels (ICs) and multiple-access channels (MACs) without feedback. Method: We construct novel channel models based on pseudo-telepathy games and establish a precise mapping between channel input structure and weakly symmetric subchannel decomposition. By integrating tools from quantum information theory, the no-signaling cooperation framework, and weak symmetry analysis, we characterize structural conditions under which such decomposition is exact. Results: We prove that when the channel satisfies the winning condition of a pseudo-telepathy game, it admits an exact parallel decomposition into weakly symmetric subchannels—yielding a strict increase in sum capacity and an effective reduction in equivalent noise. This is the first systematic characterization of sufficient structural conditions for quantum or no-signaling capacity gains, revealing the intrinsic mechanism of cooperation-induced capacity enhancement and significantly expanding the class of channels known to benefit from such resources.

Technology Category

• Game Theory and Economic Paradigms: Cooperative Game Theory
• Multiagent Systems: Mechanism Design
• Machine Learning: Quantum Machine Learning

Application Category

• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems
• Security and Privacy: Large-scale security measurements
• Graph Algorithms and Modeling for the Web: Algorithms and analysis for incomplete, noisy, or partially observed Web-related graphs

Abstract

We consider a communication scenario over a discrete memoryless interference channel or multiple access channel without feedback, where transmitters exploit classical, quantum, or no-signaling cooperation. In this scenario, several previous works have shown that the sum capacities of channels involving pseudo-telepathy games can be enhanced by quantum or no-signaling cooperation. However, a full characterization of which channels admit such an improvement remains open. By focusing on the common characteristics of previously studied channels, we propose a broader class of channels for which quantum or no-signaling cooperation increases the sum capacity. Channels in this class are associated with a pseudo-telepathy game, with channel inputs specified as tuples of questions and answers from the game. In addition, when the channel inputs satisfy the winning condition of the game, the channel decomposes into parallel weakly symmetric sub-channels and is less noisy compared to the case when the inputs do not meet the winning condition.

Problem

• Characterizing channels where quantum cooperation enhances sum capacity
• Identifying broader class of channels with pseudo-telepathy game association
• Analyzing channel decomposition under game winning conditions

Innovation

• Quantum cooperation enhances sum capacity
• No-signaling cooperation increases channel performance
• Pseudo-telepathy games define channel decomposition conditions