Gradient dynamical systems on open surfaces and critical points of Green's functions

The equations of motion of a mechanical system subjected to nonholonomic linear constraints can be formulated in terms of a linear almost Poisson structure in a vector bundle. We study the existence of invariant measures for the system in terms of the unimodularity of this structure. In the presence of symmetries, our approach allows us to give necessary and sufficient conditions for the existence of an invariant volume, that unify and improve results existing in the literature. We present an algorithm to study the existence of a smooth invariant volume for nonholonomic mechanical systems with symmetry and we apply it to several concrete mechanical examples.

Article: 
Gradient dynamical systems on open surfaces and critical points of Green's functions
Authors: 
Alberto Enciso, Daniel Peralta-Salas
Journal: 
Arxiv
Year: 
2013
URL: 
http://arxiv.org/abs/1304.1652