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arXiv · 1603.03544

Optimal search strategies of run-and-tumble walks

Jean-Francois Rupprecht·Olivier Bénichou·Raphael Voituriez
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Abstract

The run-and-tumble walk, consisting in randomly reoriented ballistic excursions, models phenomena ranging from gas kinetics to bacteria motility. We evaluate the mean time required for this walk to find a fixed target within a 2D or 3D spherical confinement. We find that the mean search time admits a minimum as a function of the mean run duration for various types of boundary conditions and run duration distributions (exponential, power-law, deterministic). Our result stands in sharp contrast to the pure ballistic motion, which is predicted to be the optimal search strategy in the case of Poisson distributed targets.

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Jean-Francois Rupprecht, Olivier Bénichou, Raphael Voituriez. 2016-03-11. Optimal search strategies of run-and-tumble walks. https://doi.org/10.1103/physreve.94.012117

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