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Communications in Mathematical Sciences
Volume 21 (2023)
Number 7
Global-in-time stability of ground states of a pressureless hydrodynamic model of collective behaviour
Pages: 1937 – 1959
DOI: https://dx.doi.org/10.4310/CMS.2023.v21.n7.a9
Authors
Abstract
We consider a pressureless hydrodynamic model of collective behaviour, which is concerned with a density function $\rho$ and a velocity field $v$ on the torus, and is described bythe continuity equation for $\rho, \rho_t + \mathrm{div}(v \rho) = 0$, and a compressible hydrodynamic equation for $v, \rho v_t + \rho v \cdot \nabla v - \Delta v = − \rho \nabla K\rho$ with a forcing modelling collective behaviour related to the density $\rho$, where $K$ stands for the repulsive interaction potential, defined as the solution to the Poisson equation on $\mathbb{T}^d$. We show global-in-time stability of the ground state $(\rho , v)=(1,0)$ if the perturbation $(\rho_0-1 ,v_0)$ satisfies ${\lVert v_0 \rVert}_{B^{d/p-1}_{p,1}(\Theta^d )} + {\lVert \rho_0-1 \rVert}_{B^{d/p}_{p,1}(\Theta^d )} \leq \epsilon$, where $p\in (\min (d/2,2),d)$ and $\epsilon >0$ is sufficiently small.
Keywords
pressureless hydrodynamic model, stability, collective behaviour, Besov spaces, repulsive system
2010 Mathematics Subject Classification
35A01, 35A02, 35B20, 35B35, 35E15, 35K57, 35Q70, 35Q92
P.B.M. was supported by the Polish National Science Centre’s Grant No. 2018/30/M/ST1/00340 (HARMONIA), and W.S.O. was supported in part by the Simons Foundation.
Received 3 November 2022
Accepted 25 January 2023
Published 9 October 2023