An extension of a boundedness result for singular integral operators

Abstract

We study some operators originating from classical Littlewood–Paley the- ory. We consider their modification with respect to our discontinuous setup, where the un- derlying process is the product of a one-dimensional Brownian motion and a d-dimensional symmetric stable process. Two operators in focus are the G? and area functionals. Using the results obtained in our previous paper, we show that these operators are bounded on Lp. Moreover, we generalize a classical multiplier theorem by weakening its conditions on the tail of the kernel of singular integrals.