A Note on the Boundedness of Riesz Transform for Some Subelliptic Operators

作者:Baudoin Fabrice*; Garofalo Nicola
来源:International Mathematics Research Notices, 2013, (2): 398-421.
DOI:10.1093/imrn/rnr271

摘要

Let M be a smooth connected noncompact manifold endowed with a smooth measure mu and a smooth locally subelliptic diffusion operator L satisfying L1=0, and that is symmetric with respect to mu. We show that if L satisfies, with a nonnegative curvature parameter (1), the generalized curvature inequality in (2.9), then the Riesz transform is bounded in L-p(M) for every p > 1, that is
parallel to root Gamma((-L)(-1/2)f)parallel to(p) <= C-p parallel to f parallel to(p,) f is an element of c(0)(infinity)(M)
where Gamma is the carre du champ associated to L. Our results apply in particular to all Sasakian manifolds whose horizontal Tanaka-Webster Ricci curvature is nonnegative, all Carnot groups with step two, and wide subclasses of principal bundles over Riemannian manifolds whose Ricci curvature is nonnegative.

  • 出版日期2013