Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9500776 | Journal of Approximation Theory | 2005 | 16 Pages |
Abstract
We consider probability measures, dμ=w(θ)dθ2Ï+dμs, on the unit circle, âD, with Verblunsky coefficients, {αj}j=0â. We prove for θ1â θ2 in [0,2Ï) thatâ«[1-cos(θ-θ1)][1-cos(θ-θ2)]logw(θ)dθ2Ï>-âif and only ifâj=0â(δ-e-iθ2)(δ-e-iθ1)αj2+|αj|4<â,where δ is the left shift operator (δβ)j=βj+1. We also prove thatâ«(1-cosθ)2logw(θ)dθ2Ï>-âif and only ifâj=0â|αj+2-2αj+1+αj|2+|αj|6<â.
Related Topics
Physical Sciences and Engineering
Mathematics
Analysis
Authors
Barry Simon, Andrej Zlatoš,