2017/11/25 by Andrei V. Vasin, Vasin, Andrei V.
Mathematics · #Advanced Harmonic Analysis Research #Nonlinear Partial Differential Equations #Analytic and geometric function theory
paper · pdf · doi:10.48550/arxiv.1711.09303
Given a Lipschitz domain D⊂ ℝd, a Calderón-Zygmund operator T and a modulus of continuity ω(x), we solve a problem when the restricted operator TDf=T(fχD)χD sends the Campanato space Cω(D) into itself. The solution is a T1 type sufficient and necessary condition for the characteristic function χD of D: (TχD)χD ∈ Cω(D), assumed ω(x)= ω(x)/∫x1 ω(t)dt/t. To check the hypotheses of T1 theorem we need extra restrictions on both the boundary of D and the operator T. It is proved that the restricted Calderón-Zygmund operator TD with the even kernel is bounded on Cω(D), provided D be C1,ω-smooth domain. This result is sharp.