Codice  QDD 92 
Titolo  L^{p} and Schauder estimates for nonvariational operators structured on Hörmander vector fields with drift 
Data  20110329 
Autore/i  Bramanti, M.; Zhu, M. 
Link  Download full text 
Abstract  We consider linear second order nonvariational partial differential operators of the kind a_{ij}X_{i}X_{j}+X_{0}, on a bounded domain of R^{n}, where the X_{i} s (i=0,1,2,...,q, n>q+1) are real smooth vector fields satisfying Hörmander s condition and a_{ij} (i,j=1,2,...,q) are real valued, bounded measurable functions, such that the matrix {a_{ij}} is symmetric and uniformly positive. We prove that if the coefficients a_{ij} are Hölder continuous with respect to the distance induced by the vector fields, then local Schauder estimates on X_{i}X_{j}u, X_{0}u hold; if the coefficients belong to the space VMO with respect to the distance induced by the vector fields, then local L^{p} estimates on X_{i}_{j}u, X_{0}u hold. The main novelty of the result is the presence of the drift term X_{0}, so that our class of operators covers, for instance, KolmogorovFokkerPlanck operators. 
