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Entropy by Neighbor Distance as a New Measure for Characterizing Spatiotemporal Orders in Microscopic Collective
Yulei Fu1, Zongyuan Wu1,2, Sirui Zhan1,3
1University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240, China.
A new measure using entropy of neighbor distances effectively characterizes order in collective systems. This method reveals phase transitions and steady states in boids, colloids, and robotic swarms.
Area of Science:
- Collective behavior
- Complex systems
- Statistical physics
Background:
- Collective systems exhibit self-organization into ordered spatiotemporal patterns.
- Understanding self-organization principles requires robust measures of pattern order.
Purpose of the Study:
- To introduce and evaluate a novel measure for characterizing order in collective systems.
- To assess the measure's sensitivity in identifying phase transitions and steady states.
Main Methods:
- Utilized a novel measure based on the entropy of neighbor distance distributions.
- Applied the measure to diverse systems: simulated boids, active colloids, and robotic swarms.
Main Results:
- The entropy-based measure effectively characterized order across all studied systems.
- The measure demonstrated sensitivity in detecting active phase transitions.
- The measure successfully distinguished between different steady states in collective patterns.
Conclusions:
- Entropy by neighbor distance is a valuable tool for analyzing collective pattern order.
- This measure can aid in understanding biological swarms like bird flocks.
- The measure has potential applications in the design of robotic swarms.
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