Abstract
We study the large-time behavior of continuum alignment dynamics based on Cucker–Smale (CS)-type interactions which involve short-range kernels, that is, communication kernels with support much smaller than the diameter of the crowd. We show that if the amplitude of the interactions is larger than a finite threshold, then unconditional hydrodynamic flocking follows. Since we do not impose any regularity nor do we require the kernels to be bounded, the result covers both regular and singular interaction kernels.Moreover, we treat initial densities in the general class of compactly supported measures which are required to have positive mass on average (over balls at small enough scale), but otherwise vacuum is allowed at smaller scales. Consequently, our arguments of hydrodynamic flocking apply, mutatis mutandis, to the agent-based CS model with finitely many Dirac masses. In particular, discrete flocking threshold is shown to depend on the number of dense clusters of communication but otherwise does not grow with the number of agents.
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Here and below we use \(\delta \cdot \) to denote fluctuations, \(\delta W\equiv (\delta W)({{\mathbf {x}}},{{\mathbf {y}}}):=W({{\mathbf {x}}})-W({{\mathbf {y}}})\) with the corresponding weighted norms taken on the product space \({{\mathcal {S}}}\times {{\mathcal {S}}}\), e.g., \(|\delta {{\mathbf {u}}}|^2_2= \int |{{\mathbf {u}}}({{\mathbf {x}}})-{{\mathbf {u}}}({{\mathbf {y}}})|^2 \, \text{ d }\rho ({{\mathbf {x}}})\, \text{ d }\rho ({{\mathbf {y}}})\). Likewise, \((\delta {{\mathbf {v}}})_{ij}={{\mathbf {v}}}_i-{{\mathbf {v}}}_j\) with \(|\delta {{\mathbf {v}}}|_\infty =\max _{i,j}|{{\mathbf {v}}}_i-{{\mathbf {v}}}_j|\) etc.
Recall that \(\rho \) is a probability measure
\({{\mathbf {x}}}_\pm \) need not be unique — any extreme location will suffice.
References
Carrillo, J.A., Choi, Y.P., Mucha, P.B., Peszek, J.: Sharp conditions to avoid collisions in singular Cucker–Smale interactions. Nonlinear Anal. 37, 317–328 (2017)
Carrill, J.A., Fornasier, M., Toscani, G., Veci, F.: Particle, kinetic, and hydrodynamic models of swarming. In: Naldi, G., Pareschi, L., Toscan, G. (eds.) Mathematical Modeling of Collective Behavior in Socio-Economic and Life Sciences, pp. 297–336. Birkhauser, Basel (2010)
Carrillo, J.A., Choi, Y.P., Tadmor, E., Tan, C.: Critical thresholds in 1D Euler equations with non-local forces. Math. Models Methods Appl. Sci. 26(1), 185–206 (2016)
Cucker, F., Smale, S.: Emergent behavior in flocks. IEEE Trans. Autom. Control 52(5), 852–862 (2007)
Cucker, F., Smale, S.: On the mathematics of emergence. Jpn. J. Math. 2(1), 197–227 (2007)
Danchin, R., Mucha P.B., Peszek, J., Wróblewski B.: Regular solutions to the fractional Euler alignment system in the Besov spaces framework. arXiv:1804.07611 (2018)
Do, T., Kiselev, A., Ryzhik, L., Tan, C.: Global regularity for the fractional Euler alignment system. Arch. Ration. Mech. Anal. 228(1), 1–37 (2018)
Figalli, A., Kang, M.-J.: A rigorous derivation from the kinetic Cucker–Smale model to the pressureless Euler system with nonlocal alignment. arXiv:1702.08087v1 (2017)
Ha, S.-Y., Ha, T., Kim, J.-H.: Emergent behavior of a Cucker–Smale type particle model with nonlinear velocity couplings. IEEE Trans. Autom. Control 55(7), 1679–1683 (2010)
Ha, S.-Y., Kim, J., Park, J., Zhang, X.: Uniform stability and mean-field limit for the augmented Kuramoto model. NHM 13(2), 297–322 (2018)
Ha, S.-Y., Liu, J.-G.: A simple proof of the Cucker–Smale flocking dynamics and mean-field limit. Commun. Math. Sci. 7(2), 297–325 (2009)
Ha, S.-Y., Tadmor, E.: From particle to kinetic and hydrodynamic descriptions of flocking. Kinet. Relat. Models 1(3), 415–435 (2008)
Haskovec, J.: Flocking dynamics and mean-field limit in the Cucker–Smale type model with topological interactions. Phys. D 261(15), 42–51 (2013)
He, S., Tadmor, E.: Global regularity of two-dimensional flocking hydrodynamics. Comptes Rendus Math. I(355), 795–805 (2017)
Jin, C.: Flocking of the Motsch–Tadmor model with a cut-off interaction function. J. Stat. Phys. 171, 345–360 (2018)
Motsch, S., Tadmor, E.: A new model for self-organized dynamics and its flocking behavior. J. Stat. Phys. 144(5), 932–947 (2011)
Motsch, S., Tadmor, E.: Heterophilious dynamics enhances consensus. SIAM Rev. 56(4), 577–621 (2014)
Mucha, P.B., Peszek, J.: The Cucker–Smale equation: singular communication weight, measure-valued solutions and weak-atomic uniqueness. Arch. Ration. Mech. Anal. 227, 273–308 (2018)
Peszek, J.: Existence of piecewise weak solutions of a discrete Cucker–Smale’s flocking model with a singular communication weight. J. Differ. Equ. 257, 2900–2925 (2014)
Peszek, J.: Discrete Cucker–Smale flocking model with a weakly singular weight. SIAM J. Math. Anal. 47(5), 3671–3686 (2015)
Poyato, D., Soler, J.: Euler-type equations and commutators in singular and hyperbolic limits of kinetic Cucker–Smale models. Math. Models Methods Appl. Sci. 27(6), 1089–1152 (2017)
Shvydkoy, R.: Global existence and stability of nearly aligned flocks. arXiv:1802.08926 (2018)
Shvydkoy, R., Tadmor, E.: Eulerian dynamics with a commutator forcing. Trans. Math. Appl. 1(1), tnx001 (2017)
Shvydkoy, R., Tadmor, E.: Eulerian dynamics with a commutator forcing II: flocking. Discret. Contin. Dyn. Syst. 37(11), 5503–5520 (2017)
Shvydkoy, R., Tadmor, E.: Eulerian dynamics with a commutator forcing III: fractional diffusion of order \(0< \alpha >1\). Phys. D 376–377, 131–137 (2018)
Shvydkoy, R., Tadmor, E.: Topological models for emergent dynamics with short-range interactions. arXiv:1806.01371 (2019)
Tadmor, E., Tan, C.: Critical thresholds in flocking hydrodynamics with non-local alignment. Philos. Trans. R. Soc. Lond. Ser. A 372(2028), 20130401 (2014)
Tan, C.: Singularity formation for a fluid mechanics model with nonlocal velocity. arXiv:1708.09360v2 (2019)
Acknowledgements
Research was supported by NSF grants DMS16-13911, RNMS11-07444 (KI-Net) and ONR Grant N00014-1812465. JP was also supported by the Polish MNiSW grant Mobilność Plus no. 1617/MOB/V/2017/0.
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Communicated by Eric Carlen.
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Morales, J., Peszek, J. & Tadmor, E. Flocking With Short-Range Interactions. J Stat Phys 176, 382–397 (2019). https://doi.org/10.1007/s10955-019-02304-5
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DOI: https://doi.org/10.1007/s10955-019-02304-5
Keywords
- Alignment
- Cucker–Smale
- Agent-based system
- Large-crowd hydrodynamics
- Interaction kernels
- Short-range
- Chain connectivity
- Flocking
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