Information interference driven by environmental activity

TL;DR

This paper investigates how environmental activity influences the mutual information between interacting particles, revealing that environmental and internal interactions can interfere constructively or destructively, depending on system parameters and nonlinearities.

Contribution

It introduces a decomposition of mutual information into internal, environmental, and interference components, analyzing their behavior in linear and nonlinear interaction models.

Findings

Interference sign depends on internal coupling in linear systems.

Nonlinear interactions exhibit both constructive and destructive interference.

Asymmetry in environmental coupling affects information interference.

Abstract

Real-world systems are shaped by both their complex internal interactions and the changes in their noisy environments. In this work, we study how a shared active bath affects the statistical dependencies between two interacting Brownian particles by evaluating their mutual information. We decompose the mutual information into three terms: information stemming from the internal interactions between the particles; information induced by the shared bath, which encodes environmental changes; a term describing information interference that quantifies how the combined presence of both internal interactions and environment either masks (destructive interference) or boosts (constructive interference) information. By studying exactly the case of linear interactions, we find that the sign of information interference depends solely on that of the internal coupling. However, when internal interactions are described by a nonlinear activation function, we show that both constructive and destructive interference appear depending on the interplay between the timescale of the active environment, the internal interactions, and the environmental coupling. Finally, we show that our results generalize to hierarchical systems where asymmetric couplings to the environment mimic the scenario where the active bath is only partially accessible to one particle. This setting allows us to quantify how this asymmetry drives information interference. Our work underscores how information and functional relationships in complex multi-scale systems are fundamentally shaped by the environmental context.