The comparsion principle for viscosity solutions of fully nonlinear subelliptic equations in Carnot groups
arXiv:math/0309078
Abstract
For any Carnot group and a bounded domain , we prove that viscosity solutions in $C(\bar\Om)$ of the fully nonlinear subelliptic equation are unique when $F\in C(R\times R^m\times {\Cal S}(m))$ satisfies (i) is degenerate subelliptic and decreasing in or (ii) is uniformly subelliptic and nonincreasing in . This extends Jensen's uniqueness theorem from the Euclidean space to the sub-Riemannian setting of the Carnot group.
15 pages