An axiomatic measure of one-way quantum information

TL;DR

This paper introduces an algorithm and an information-theoretic measure to detect and quantify one-way quantum information transfer in complex quantum systems, enabling causal analysis in many-body dynamics.

Contribution

It presents a novel algorithm and a set of axioms for quantifying one-way quantum information transfer, applicable to complex quantum networks.

Findings

Successfully detects direction and orientation of quantum information transfer.

Quantifies one-way quantum information transfer satisfying key axioms.

Reconstructs causal patterns in many-body quantum systems.

Abstract

I introduce an algorithm to detect one-way quantum information between two interacting quantum systems, i.e. the direction and orientation of the information transfer in arbitrary quantum dynamics. I then build an information-theoretic quantifier of one-way information which satisfies a set of desirable axioms. In particular, it correctly evaluates whether correlation implies one-way quantum information, and when the latter is transferred between uncorrelated systems. In the classical scenario, the quantity measures information transfer between random variables. I also generalize the method to identify and rank concurrent sources of quantum information flow in many-body dynamics, enabling to reconstruct causal patterns in complex networks.