We study the boundedness of weighted multilinear operators given by products of finite vectors of Calderon-Zygmund operators. We also investigate weighted estimates for bilinear operators related to Schrodinger operator.
In this paper, we characterize the weighted Hardy space related to the Schrodinger operator , with V a non-negative potential satisfying a reverse Holder inequality, by atomic decomposition and Riesz transforms. We also get a characterization of its dual space through a weighted Carleson measure. Then we prove the boundedness of some classical operators associated to on the weighted BMO space .
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.