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Updated: Jun 11, 2026
10:53
Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
Published on: March 12, 2019
From global flocking to local clustering: Interplay between velocity alignment and visual perception of active
Mohit Gaur1, Arnab Saha2,3, Subhajit Paul1
1Department of Physics and Astrophysics, University of Delhi, Delhi 110007, India.
The Journal of Chemical Physics
|June 10, 2026
Summary
Limiting an organism's vision angle in flocking models, like the Vicsek model, shifts collective motion from large, coherent clusters to fragmented ones. This fragmentation, even with short-range correlations, alters dynamics significantly, especially in low-noise environments.
Area of Science:
- Collective behavior
- Complex systems
- Statistical physics
Background:
- The Vicsek model describes flocking dynamics in living systems with local velocity alignment and noise.
- Introducing a limited vision angle breaks symmetry and introduces non-reciprocity in interactions.
Purpose of the Study:
- To investigate how limited vision angles affect collective motion and cluster formation in the Vicsek model.
- To analyze the transition from global coherent motion to fragmented clusters under varying noise levels and vision angles.
Main Methods:
- Simulations of the Vicsek model with adjustable vision angles and noise strengths.
- Analysis of polar order parameter, cluster size distributions, and velocity correlations.
- Probing steady-state properties and time evolution of system dynamics.
Main Results:
- Decreasing vision angle in low noise leads to fragmentation of large clusters into smaller, locally ordered ones.
- In high noise, decreasing vision angle results in a homogeneous, disordered state.
- Short-range correlations persist within small clusters even at limited vision angles.
Conclusions:
- Limited vision angles fundamentally alter flocking dynamics, promoting fragmentation over global coherence.
- The interplay between noise and vision angle dictates the emergence of ordered or disordered collective states.
- Cognitive perception, modeled by vision angle, significantly impacts emergent collective behavior.
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