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  • Open Access

Wave-like statistics from classical active particles with internal degrees of freedom

Rahil N. Valani*

  • Rudolf Peierls Centre for Theoretical Physics, Parks Road, University of Oxford, Oxford OX1 3PU, United Kingdom

  • *Contact author: rahil.valani@physics.ox.ac.uk
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Phys. Rev. E 114, 025407 – Published 13 August, 2026

DOI: https://doi.org/10.1103/qkv2-vnkj

Abstract

Wave-like spatial statistics in walking-droplet systems are often associated with wave-mediated interactions and wave-memory effects. Here we explore how similar statistical structure can arise from the low-dimensional nonlinear dynamics of an inertial active particle with internal degrees of freedom. In this framework, steady propulsion corresponds to internal-state fixed points whose spiral or transiently chaotic relaxation organizes oscillatory ensemble densities. Local perturbations then generate wave-like statistics in both open and closed geometries, suggesting that wave-like ensemble behavior may emerge more generally from internal-state attractor dynamics in inertial active matter.

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Phys. Rev. E 114, 025407– Published 13 August, 2026
  • Received 28 December 2025
  • Accepted 29 July 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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