An Alexander-like theorem for a particle model with inelastic collisions
Abstract
We consider a finite system of hard spheres that collide inelastically according to a particular model, losing a fixed amount of kinetic energy at each collision. We develop the theory of the Transport-Collision-Transport (TCT) dynamics, which allows to study precisely the evolution of the Lebesgue measure in the phase space under the action of the flows of particle systems that can interact via instantaneous binary collision. We show that the scattering mapping associated to the inelastic hard sphere system we introduce preserves locally the Lebesgue measure in the velocity space, in spite of the fact that a positive amount of kinetic energy is lost at each inelastic collision. We prove the analog of Alexander's theorem for our model, which allows us to deduce the global well-posedness of the trajectories, for almost every initial datum.
Cite
@article{arxiv.2403.02162,
title = {An Alexander-like theorem for a particle model with inelastic collisions},
author = {Théophile Dolmaire and Juan J. L. Velázquez},
journal= {arXiv preprint arXiv:2403.02162},
year = {2025}
}
Comments
33 pages. Addition of the definition of the Transport-Collision-Transport (TCT) dynamics, and the TCT volume formula, in order to estimate the evolution of the Lebesgue measure in the phase space under the action of the flow of the particle system