| Affiliation: | 1.Department of Mathematics,Brown University,Providence,USA;2.Department of Mathematics, Lefschetz Center for Dynamical Systems,Brown University,Providence,USA |
| Abstract: | We consider a rigid body colliding with a continuum of particles. We assume that the body is moving at a velocity close to an equilibrium velocity ({V_{infty}}) and that the particles colliding with the body reflect diffusely, that is, probabilistically with some probability distribution K. We find a condition that is sufficient and almost necessary that the collective force of the colliding particles reverses the relative velocity V(t) of the body, that is, changes the sign of ({V(t)-V_{infty}}), before the body approaches equilibrium. Examples of both reversal and irreversal are given. This is in strong contrast with the pure specular reflection case in which only reversal happens. |
