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Collective ballistic motion explains fast aggregation in adhesive active matter
Emanuel F Teixeira1,2, Pablo de Castro3,4,5, Carine P Beatrici2
1Leiden University, Huygens-Kamerlingh Onnes Laboratory, P. O. Box 9504, 2300 RA Leiden, The Netherlands.
Physical Review. E
|July 24, 2026
Summary
Active particle systems aggregate ballistically via flocking, mimicking cell tissue formation. This kinetic transition explains diverse cellular aggregation behaviors and aids understanding of tissue organization.
Area of Science:
- Physics
- Biophysics
- Materials Science
Background:
- Cellular aggregation is crucial for tissue formation.
- Existing models do not fully explain the diverse aggregation behaviors observed in biological systems.
Purpose of the Study:
- To investigate the aggregation dynamics of active, self-aligning, adhesive particles.
- To provide a physical framework for understanding cellular aggregation and tissue organization.
Main Methods:
- Analytical modeling of particle interactions and dynamics.
- Numerical simulations of active particle systems.
- Comparison with experimental data on cellular aggregation.
Main Results:
- Identified a flocking transition leading to ballistic aggregation in active particle systems.
- Discovered distinct noncollective kinetic regimes, including long-lived transients.
- Developed a framework explaining observed aggregation exponents in cellular systems.
Conclusions:
- The flocking transition in active particle systems offers a mechanism for rapid aggregation.
- The findings provide insights into physical principles governing timely tissue organization.
- This work bridges the gap between active matter physics and developmental biology.
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