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Onset of collective and cohesive motion.
It is found that this phase transition, in two space dimensions, is always discontinuous, including for the minimal model of Vicsek et al. for which a nontrivial critical point was previously advocated.
Characterizing dynamics with covariant Lyapunov vectors.
A general method to determine covariant Lyapunov vectors in both discrete- and continuous-time dynamical systems is introduced. This allows us to address fundamental questions such as the degree of
Deciphering Interactions in Moving Animal Groups
Using video tracks of fish shoal in a tank, it is shown how a careful, incremental analysis at the local scale allows for the determination of the stimulus/response function governing an individual's moving decisions, yielding a novel schooling model whose parameters are all estimated from data.
Large-scale finite-wavelength modulation within turbulent shear flows.
We show that turbulent "spirals" and "spots" observed in Taylor-Couette and plane Couette flow correspond to a turbulence-intensity modulated finite-wavelength pattern which in every respect fits the
Collective motion of self-propelled particles interacting without cohesion.
The onset of collective motion in Vicsek-style self-propelled particle models in two and three space dimensions is studied in detail and shown to be discontinuous (first-order-like), and the properties of the ordered, collectively moving phase are investigated.
Statistical analysis of the transition to turbulence in plane Couette flow
Abstract:We argue on general grounds that the transition to turbulence in plane Couette flow is best studied experimentally at a statistical level. We present such a statistical analysis of
Modeling collective motion: variations on the Vicsek model
We argue that the model introduced by Vicsek et al. in which self-propelled particles align locally with neighbors is, because of its simplicity, central to most studies of collective motion or
Spatiotemporal intermittency regimes of the one-dimensional complex Ginzburg-Landau equation
Completing an earlier work, the 'phase diagram' of the one-dimensional complex Ginzburg-Landau equation is presented. In the Benjamin-Feir stable region, spatiotemporal intermittency regimes are