## Illinois Journal of Mathematics

### Some properties of Hölder surfaces in the Heisenberg group

#### Abstract

It is a folk conjecture that for $\alpha>1/2$ there is no $\alpha$-Hölder surface in the subRiemannian Heisenberg group. Namely, it is expected that there is no embedding from an open subset of $\mathbb{R}^{2}$ into the Heisenberg group that is Hölder continuous of order strictly greater than $1/2$. The Heisenberg group here is equipped with its Carnot–Carathéodory distance. We show that, in the case that such a surface exists, it cannot be of essential bounded variation and it intersects some vertical line in at least a topological Cantor set.

#### Article information

Source
Illinois J. Math., Volume 57, Number 1 (2013), 229-249.

Dates
First available in Project Euclid: 23 June 2014

Permanent link to this document
https://projecteuclid.org/euclid.ijm/1403534494

Digital Object Identifier
doi:10.1215/ijm/1403534494

Mathematical Reviews number (MathSciNet)
MR3224569

Zentralblatt MATH identifier
1294.53033

#### Citation

Le Donne, Enrico; Züst, Roger. Some properties of Hölder surfaces in the Heisenberg group. Illinois J. Math. 57 (2013), no. 1, 229--249. doi:10.1215/ijm/1403534494. https://projecteuclid.org/euclid.ijm/1403534494

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