RT Journal Article SR 00 ID 10.1007/s10955-017-1882-z A1 Blanchet, Adrien A1 Degond, Pierre T1 Kinetic models for topological nearest-neighbor interactions JF Journal of Statistical Physics YR 2017 FD 2017-12 VO 169 IS 5 SP 929 OP 950 K1 rank-based interaction K1 spatial diffusion equation K1 continuity equation K1 concentration of measure AB We consider systems of agents interacting through topological interactions. These have been shown to play an important part in animal and human behavior. Precisely, the system consists of a finite number of particles characterized by their positions and velocities. At random times a randomly chosen particle, the follower adopts the velocity of its closest neighbor, the leader. We study the limit of a system size going to infinity and, under the assumption of propagation of chaos, show that the limit kinetic equation is a non-standard spatial diffusion equation for the particle distribution function. We also study the case wherein the particles interact with their K closest neighbors and show that the corresponding kinetic equation is the same. Finally, we prove that these models can be seen as a singular limit of the smooth rank-based model previously studied in [10]. The proofs are based on a combinatorial interpretation of the rank as well as some concentration of measure arguments. PB Kluwer SN 1572-9613 LK https://publications.ut-capitole.fr/id/eprint/25738/ UL http://tse-fr.eu/pub/32176