A free boundary problem for the parabolic Poisson kernel

Autor: Max Engelstein
Rok vydání: 2017
Předmět:
Zdroj: Advances in Mathematics. 314:835-947
ISSN: 0001-8708
DOI: 10.1016/j.aim.2017.04.032
Popis: We study parabolic chord arc domains, introduced by Hofmann, Lewis and Nystr\"om, and prove a free boundary regularity result below the continuous threshold. More precisely, we show that a Reifenberg flat, parabolic chord arc domain whose Poisson kernel has logarithm in VMO must in fact be a vanishing chord arc domain (i.e. satisfies a vanishing Carleson measure condition). This generalizes, to the parabolic setting, a result of Kenig and Toro and answers in the affirmative a question left open in the aforementioned paper of Hofmann et al. A key step in this proof is a classification of "flat" blowups for the parabolic problem.
Comment: 91 pages. Comments welcome
Databáze: OpenAIRE