Geometry Seminar

 

Singular Cauchy Integrals and

Hilbert transforms on Curves and Surfaces

 

Professor Qian Tao
University of Macau

 

Abstract

There could be some confusion between Cauchy singular integrals and Hilbert transforms on curves and surfaces. We justify the terminology Hilbert transforms by defining it through Hardy spaces, following Bell and the others, and prove their Lp boundedness, where the rage of p depends on the Lipschitz constant of the curve or surface under study.  Next we deduce he inner and outer conjugate Poisson kernels, and thus the inner and outer Schwarz kernels on the unit sphere, and the Fourier multiplier representations of the inner and outer Hilbert transforms on the sphere.  We finally prove the boundedness in all Lp,    1 < p < ¥, of the Hilbert transforms on the sphere from the theory of the operator algebra of singular integrals with monogenic Calderon-Zygmund type kernels.

The talk is based on a joint work between the speaker, A. Axelsson, K-I. Kou and Y. Yan.

 

Date:

May 3, 2007 (Thursday)

Time:

3:00 – 4:00pm

Place:

Room 517, Meng Wah Complex, HKU

 

 

 

All are welcome