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Particle velocity controls phase transitions in contagion dynamics
Jorge P Rodríguez1, Fakhteh Ghanbarnejad2,3, Víctor M Eguíluz4
1Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (CSIC-UIB), Palma de Mallorca, E-07122, Spain. jorgeprodriguezg@gmail.com.
Scientific Reports
|April 25, 2019
Summary
Particle movement influences contagion dynamics. Optimal velocity maximizes epidemic thresholds, while lower speeds increase outbreak size. Cooperative infections show velocity-dependent phase transitions.
Area of Science:
- Complex systems
- Epidemiology
- Statistical physics
Background:
- Particle proximity is crucial for interactions and contagion.
- Particle movement alters neighbor configurations, influencing interaction sequences.
- Pathogen movement facilitates both infection spread and strain co-location.
Purpose of the Study:
- To investigate the impact of particle velocity on contagion phase transitions.
- To analyze single and cooperative infection dynamics under varying velocities.
- To identify optimal velocities for epidemic control and understand transition mechanisms.
Main Methods:
- Mathematical modeling of particle movement and contagion.
- Analysis of phase transitions in epidemic thresholds.
- Simulation of single and cooperative infection scenarios.
Main Results:
- An optimal particle velocity was identified, maximizing the epidemic threshold.
- Decreasing velocity below the optimum leads to larger outbreaks.
- Cooperative infections exhibit continuous transitions at low velocities and discontinuous transitions at higher velocities.
Conclusions:
- Particle velocity is a critical parameter in contagion dynamics.
- Understanding velocity-dependent transitions can inform epidemic control strategies.
- The study elucidates mechanisms driving contagion spread and strain interactions.
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