Gauge-independent Hamiltonian reduction of constrained systems.
Generalized Hamiltonian dynamics after Dirac and Tulczyjew
Dirac's generalized Hamiltonian dynamics is given an accurate geometric formulation as an implicit differential equation and is compared with Tulczyjew's formulation of dynamics. From the comparison it follows that Dirac's equation-unlike Tulczyjew's-fails to give a complete picture of the real laws of classical and relativistic dynamics.
Generalized Lagrange-d'Alembert Principle
Geometry of non-holonomic diffusion
We study stochastically perturbed non-holonomic systems from a geometric point of view. In this setting, it turns out that the probabilistic properties of the perturbed system are intimately linked to the geometry of the constraint distribution. For -Chaplygin systems, this yields a stochastic criterion for the existence of a smooth preserved measure. As an application of our results we consider the motion planning problem for the noisy two-wheeled robot and the noisy snakeboard.