8 papers · 1 filter
A fast dynamo on the three-torus
Michele Coti Zelati, Massimo Sorella, David Villringer
We study the kinematic dynamo equation on the three-torus and provide a rigorous proof of fast dynamo action for a time-periodic, divergence-free, Lipschitz velocity field. Our con…
Stability analysis for active Brownian particle models
Michele Coti Zelati, Lucas Ertzbischoff, David Gerard-Varet
We carry out a comprehensive linear stability analysis of active Brownian particle systems around a constant homogeneous state. These scalar models, being important prototypes for…
A Stochastic RAGE Theorem and Enhanced Dissipation for Transport Noise
Michele Coti Zelati, Martin Hairer, David Villringer
We prove a stochastic version of the classical RAGE theorem that applies to the two-point motion generated by noisy transport equations. As a consequence, we identify a necessary a…
Alpha-unstable flows and the fast dynamo problem
Michele Coti Zelati, Massimo Sorella, David Villringer
We construct a time-independent, incompressible, and Lipschitz-continuous velocity field in that generates a fast kinematic dynamo - an instability characterized by…
On the stability of viscous three-dimensional rotating Couette flow
Michele Coti Zelati, Augusto Del Zotto, Klaus Widmayer
We study the stability of Couette flow in the 3d Navier-Stokes equations with rotation, as given by the Coriolis force. Hereby, the nature of linearized dynamics near Couette flow…
Three-dimensional exponential mixing and ideal kinematic dynamo with randomized ABC flows
Michele Coti Zelati, VÃctor Navarro-Fernández
In this work we consider the Lagrangian properties of a random version of the Arnold-Beltrami-Childress (ABC) in a three-dimensional periodic box. We prove that the associated flow…