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Updated: Jul 11, 2025
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
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Non-reciprocity across scales in active mixtures.
Alberto Dinelli1, Jérémy O'Byrne1,2, Agnese Curatolo3
1Université Paris Cité, Laboratoire Matière et Systèmes Complexes (MSC), UMR 7057 CNRS, F-75205, Paris, France.
Nature Communications
|November 4, 2023
Summary
Non-reciprocal interactions in active matter can lead to complex behaviors. This study shows how these interactions can simplify at larger scales, enabling equilibrium descriptions and predicting system dynamics.
Area of Science:
- Physics
- Biophysics
- Complex Systems
Background:
- Active matter systems exhibit mediated interactions not obeying Newton's third law, leading to non-reciprocity.
- Non-reciprocal interactions (NRI) create complex emergent behaviors difficult to model from microscopic principles, especially out of equilibrium.
Purpose of the Study:
- To investigate how non-reciprocal interactions in bacterial mixtures behave during coarse-graining.
- To develop a theoretical framework connecting microscopic and macroscopic dynamics of systems with NRI.
- To predict large-scale behaviors like phase separation and demixing from microscopic descriptions.
Main Methods:
- Analysis of bacterial mixtures with quorum-sensing and chemotaxis as NRI.
- Explicitly relating microscopic dynamics to macroscopic behavior.
- Deriving conditions for the fading or survival of non-reciprocity upon coarse-graining.
Main Results:
- Identified conditions under which non-reciprocity fades, allowing for equilibrium descriptions of active matter.
- Quantitatively explained simulations of phase separation, demixing, and multi-phase coexistence without fitting parameters.
- Derived conditions for NRI survival, predicting diverse dynamical patterns and phase diagrams.
Conclusions:
- The fate of non-reciprocity across different scales is crucial for understanding active matter.
- A unified theoretical framework can quantitatively predict the behavior of systems with NRI.
- This work bridges microscopic details and macroscopic emergent phenomena in non-reciprocal systems.
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