Order and Information in the Patterns of Spinning Magnetic Micro-disks at the Air-water Interface

TL;DR

This study uses spinning magnetic micro-disks at the air-water interface to explore how information, measured by Shannon entropy, relates to structural organization in self-organizing systems, revealing direct links without explicit interaction knowledge.

Contribution

It demonstrates a novel experimental approach linking information and structure through Shannon entropy in a self-organizing micro-disk system, without requiring detailed interaction data.

Findings

Shannon entropy effectively characterizes structural changes.

Direct link established between information and structure.

Micro-disk patterns exhibit varying degrees of order.

Abstract

The application of the Shannon entropy to study the relationship between information and structures has yielded insights into molecular and material systems. However, the difficulty in directly observing and manipulating atoms and molecules hampers the ability of these systems to serve as model systems for further exploring the links between information and structures. Here, we use, as a model experimental system, hundreds of spinning magnetic micro-disks self-organizing at the air-water interface to generate various spatiotemporal patterns with varying degrees of orders. Using the neighbor distance as the information-bearing variable, we demonstrate the links among information, structure, and interactions. Most importantly, we establish a direct link between information and structure without using explicit knowledge of interactions. Finally, we show that the Shannon entropy by neighbor distances is a powerful observable in characterizing structural changes. Our findings are relevant for analyzing natural self-organizing systems and for designing collective robots.