Linear ODEs and -modules, solving and decomposing equations using symmetry methods.
Given a second order differential equation on a manifold we find necessary and sufficient conditions for the existence of a coordinate system in which the system is linear. The main tool to be used is a linear connection defined by the system of differential equations.
The aim of the paper is to provide a linearization approach to the -control problems. We begin by proving a semigroup-type behaviour of the set of constraints appearing in the linearized formulation of (standard) control problems. As a byproduct we obtain a linear formulation of the dynamic programming principle. Then, we use the approach and the associated linear formulations. This seems to be the most appropriate tool for treating problems in continuous and lower semicontinuous setting.
The aim of the paper is to provide a linearization approach to the See PDF-control problems. We begin by proving a semigroup-type behaviour of the set of constraints appearing in the linearized formulation of (standard) control problems. As a byproduct we obtain a linear formulation of the dynamic programming principle. Then, we use the See PDF approach and the associated linear formulations. This seems to be the most appropriate tool for treating See PDF problems in continuous and lower semicontinuous...
We show the change of coordinates that maps the maximally symmetric -distribution given by solutions to the and generalised Chazy equation to the flat Cartan distribution. This establishes the local equivalence between the maximally symmetric and generalised Chazy distribution and the flat Cartan or Hilbert-Cartan distribution. We give the set of vector fields parametrised by solutions to the and generalised Chazy equation and the corresponding Ricci-flat conformal scale that bracket-generate...
On a closed convex set in with sufficiently smooth () boundary, the stop operator is locally Lipschitz continuous from into . The smoothness of the boundary is essential: A counterexample shows that -smoothness is not sufficient.