English

Bulk topological states in a new collective dynamics model

Statistical Mechanics 2022-01-28 v3

Abstract

In this paper, we demonstrate the existence of topological states in a new collective dynamics model. This individual-based model (IBM) describes self-propelled rigid bodies moving with constant speed and adjusting their rigid-body attitude to that of their neighbors. In previous works, a macroscopic model has been derived from this IBM in a suitable scaling limit. In the present work, we exhibit explicit solutions of the macroscopic model characterized by a non-trivial topology. We show that these solutions are well approximated by the IBM during a certain time but then the IBM transitions towards topologically trivial states. Using a set of appropriately defined topological indicators, we reveal that the breakage of the non-trivial topology requires the system to go through a phase of maximal disorder. We also show that similar but topologically trivial initial conditions result in markedly different dynamics, suggesting that topology plays a key role in the dynamics of this system.

Keywords

Cite

@article{arxiv.2101.10864,
  title  = {Bulk topological states in a new collective dynamics model},
  author = {Pierre Degond and Antoine Diez and Mingye Na},
  journal= {arXiv preprint arXiv:2101.10864},
  year   = {2022}
}
R2 v1 2026-06-23T22:32:58.702Z