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Critical behavior of quorum-sensing active particles.
Nicoletta Gnan1,2, Claudio Maggi2,3
1ISC-CNR, Institute for Complex Systems, Piazzale A. Moro 2, I-00185, Roma, Italy. nicoletta.gnan@cnr.it.
Soft Matter
|September 28, 2022
Summary
This study investigates quorum sensing active particles, confirming they exhibit motility-induced phase separation and critical behavior. Their critical exponents align with the Ising universality class, settling a debate on active particle universality.
Area of Science:
- Statistical mechanics
- Soft matter physics
- Active matter physics
Background:
- The universality class of critical active particles remains a debated topic.
- Quorum sensing active particles serve as a key model for motility-induced phase separation.
- Mean-field theory predicts a critical point for this system under specific conditions.
Purpose of the Study:
- To numerically investigate the critical behavior of quorum sensing active particles.
- To determine if these particles belong to the Ising universality class.
- To locate the critical point of the motility-induced phase separation.
Main Methods:
- Large-scale numerical simulations were employed.
- Finite-size scaling analysis was utilized.
- Critical exponents were calculated and compared.
Main Results:
- The study confirms the occurrence of full phase separation.
- The critical point of the system was successfully located.
- Static and dynamic critical exponents were found to be consistent with the Ising universality class.
Conclusions:
- Quorum sensing active particles exhibit critical behavior belonging to the Ising universality class.
- The findings resolve the debate regarding the universality of these active particles.
- The study validates mean-field predictions for motility-induced phase separation in this model.
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