Work

Causal influence versus signaling for interacting quantum channels

Year: 2024

Type: article

Abstract: A causal relation between quantum agents, say Alice and Bob, is necessarily mediated by an interaction. Modeling the latter as a reversible quantum channel, an intervention of Alice can have causal influence on Bob's system, modifying correlations between Alice and Bob's systems. Causal influence between quantum systems necessarily allows for signaling. Here we prove a mismatch between causal influence and signaling via direct computation of the two quantities for the Cnot gate. Finally we show a continuity theorem for causal effects of unitary channels: a channel has small causal influence if it allows for small signaling. Published by the American Physical Society 2024

Source: Physical Review Research

DOI: 10.1103/physrevresearch.6.043305

Authors: Kathleen Barsse, Paolo Perinotti, Alessandro Tosini, Leonardo Vaglini

Institutions: University of Pavia, Université Paris-Saclay

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,625

Funders: Silicon Valley Community Foundation, École Normale Supérieure, Federico and Elvia Faggin Foundation, NextGenerationEU