Problems / analysis
analysis / Geometric function theory, integral means spectrum
Kraetzer's conjecture on the universal integral means spectrum
Theorem 1.1: there are constants 0<ε<1/4 and C with M−1[f′](r)≤C(1−r)−1/4+ε for every f∈S and 1/2≤r<1, so Bb(−1)<1/4=p2/4 at p=−1 and Kraetzer's formula is false. The bound needs no bounded image or boundary regularity. Not shown: the true value of Bb(−1) or any explicit gap, and nothing about p=1 or the Carleson-Jones question; Brennan's value B(−2)=1, also predicted by Kraetzer, is proved in the companion (separate entry).