## Illinois Journal of Mathematics

### Dimension of elliptic harmonic measure of snowspheres

Daniel Meyer

#### Abstract

A metric space $\mathcal{S}$ is called a quasisphere if there is a quasisymmetric homeomorphism $f : S^2\to\mathcal{S}$. We consider the elliptic harmonic measure, i.e., the push forward of $2$-dimensional Lebesgue measure by $f$. It is shown that for certain self similar quasispheres $\mathcal{S}$ (snowspheres) the dimension of the elliptic harmonic measure is strictly less than the Hausdorff dimension of $\mathcal{S}$. This result is obtained by representing the self similarity of a snowsphere by a postcritically finite rational map, and showing a corresponding result for such maps. As a corollary a metric characterization of Lattès maps is obtained. Furthermore, a method to compute the dimension of elliptic harmonic measure numerically is presented, along with the (numerically computed) values for certain examples.

#### Article information

Source
Illinois J. Math., Volume 53, Number 2 (2009), 691-721.

Dates
First available in Project Euclid: 23 February 2010

Permanent link to this document
https://projecteuclid.org/euclid.ijm/1266934799

Digital Object Identifier
doi:10.1215/ijm/1266934799

Mathematical Reviews number (MathSciNet)
MR2594650

Zentralblatt MATH identifier
1188.30026

#### Citation

Meyer, Daniel. Dimension of elliptic harmonic measure of snowspheres. Illinois J. Math. 53 (2009), no. 2, 691--721. doi:10.1215/ijm/1266934799. https://projecteuclid.org/euclid.ijm/1266934799

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