English

Singular integrals on $C_{w^*}^{1,\alpha}$ regular curves in Banach duals

Classical Analysis and ODEs 2021-10-18 v2 Functional Analysis Metric Geometry

Abstract

The modern study of singular integral operators on curves in the plane began in the 1970's. Since then, there has been a vast array of work done on the boundedness of singular integral operators defined on lower dimensional sets in Euclidean spaces. In recent years, mathematicians have attempted to push these results into a more general metric setting particularly in the case of singular integral operators defined on curves and graphs in Carnot groups. Suppose X=YX = Y^* for a separable Banach space YY. Any separable metric space can be isometrically embedded in such a Banach space via the Kuratowski embedding. Suppose Γ=γ([a,b])\Gamma = \gamma([a,b]) is a curve in XX whose ww^*-derivative is H\"{o}lder continuous and bounded away from 0. We prove that any convolution type singular integral operator associated with a 1-dimensional Calder\'{o}n-Zygmund kernel which is uniformly L2L^2-bounded on lines is LpL^p-bounded along Γ\Gamma. We also prove a version of David's ``good lambda'' theorem for upper regular measures on doubling metric spaces.

Keywords

Cite

@article{arxiv.2012.12984,
  title  = {Singular integrals on $C_{w^*}^{1,\alpha}$ regular curves in Banach duals},
  author = {Scott Zimmerman},
  journal= {arXiv preprint arXiv:2012.12984},
  year   = {2021}
}

Comments

23 pages; significant overhaul of the statement, proof, and application of the "good lambda'' result (Theorem 5.1), replaced the doubling measure assumption with upper regular; several minor changes throughout

R2 v1 2026-06-23T21:20:13.748Z