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arXiv · 2201.05476

Stable and unstable flow regimes for active fluids in the periodic setting

Christiane Bui·Christian Gesse·Jürgen Saal
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Abstract

Depending on the involved physiobiological parameters, stable or unstable behavior in active fluids is observed. In this paper a rigorous analytical justification of (in-)stability within the corresponding regimes is given. In particular, occuring instability for the manifold of ordered polar states caused by self-propulsion is proved. This represents the prerequisite for active turbulence patterns as observed in a number of applications. The approach is carried out in the periodic setting and is based on the generalized principle of linearized (in)-stability related to normally stable and normally hyperbolic equilibria.

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Christiane Bui, Christian Gesse, Jürgen Saal. 2022-01-14. Stable and unstable flow regimes for active fluids in the periodic setting. https://doi.org/10.1016/j.nonrwa.2022.103707

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