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Aging dynamics of d-dimensional locally activated random walks.
Julien Brémont1,2, Theresa Jakuszeit3, R Voituriez1,2
1<a href="https://ror.org/04zaaa143">Laboratoire de Physique Théorique de la Matière Condensée</a>, CNRS/Sorbonne Université, 4 Place Jussieu, 75005 Paris, France.
Locally activated random walks modify movement dynamics at specific sites, mimicking biological systems. This research offers a framework to analyze these complex, non-Markovian processes and their aging effects.
Area of Science:
- Physics
- Biophysics
- Mathematical Biology
Background:
- Random walks are fundamental models for diffusion and movement.
- Living systems exhibit complex movement patterns influenced by local environmental factors.
- Existing models often struggle to capture non-Markovian and aging dynamics.
Purpose of the Study:
- To develop a general analytical framework for locally activated random walks.
- To characterize statistical properties of these random walks on d-dimensional lattices.
- To identify experimental signatures of activated dynamics.
Main Methods:
- Definition of locally activated random walks with modified dynamics at activation sites.
- Analytical framework to determine statistical properties (position, dynamical parameters).
- Application to both passive (diffusive) and active (run and tumble) dynamics.
Main Results:
- Quantification of aging dynamics and potential trapping effects.
- Demonstration of strongly non-Markovian behavior.
- Identification of clear signatures characteristic of activated dynamics.
Conclusions:
- The proposed framework provides a robust method for analyzing complex biological movement.
- Activated random walks offer insights into cell migration and animal foraging behavior.
- The identified signatures can guide experimental data analysis in biophysical systems.
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