Tangents, rectifiability, and corkscrew domains
Azzam, Jonas (University of Edinburgh. School of Mathematics)
Date: |
2018 |
Abstract: |
In a recent paper, Csörnyei and Wilson prove that curves in Euclidean space of σ-finite length have tangents on a set of positive H 1-measure. They also show that a higher dimensional analogue of this result is not possible without some additional assumptions. In this note, we show that if Σ ⊆ Rd+1 has the property that each ball centered on Σ contains two large balls in different components of Σc and Σ has σ-finite H d-measure, then it has d-dimensional tangent points in a set of positive H d-measure. As an application, we show that if the dimension of harmonic measure for an NTA domain in Rd+1 is less than d, then the boundary domain does not have σ-finite H d-measure. We also give shorter proofs that Semmes surfaces are uniformly rectifiable and, if Ω ⊆ Rd+1 is an exterior corkscrew domain whose boundary has locally finite H d-measure, one can find a Lipschitz subdomain intersecting a large portion of the boundary. |
Rights: |
Tots els drets reservats. |
Language: |
Anglès |
Document: |
Article ; recerca ; Versió publicada |
Subject: |
Harmonic measure ;
Absolute continuity ;
Corkscrew domains ;
Uniform rectifiability ;
Tangent ;
Contingent ;
Semmes surfaces |
Published in: |
Publicacions matemàtiques, Vol. 62 Núm. 1 (2018) , p. 161-176 (Articles) , ISSN 2014-4350 |
Adreça alternativa: https://raco.cat/index.php/PublicacionsMatematiques/article/view/329932
DOI: 10.5565/PUBLMAT6211808
The record appears in these collections:
Articles >
Published articles >
Publicacions matemàtiquesArticles >
Research articles
Record created 2017-12-05, last modified 2023-07-23