Abstract
We exhibit a class of Schottky subgroups of \(\mathbf {PU}(1,n)\) (\(n \ge 2\)) which we call well-positioned and show that the Hausdorff dimension of the limit set \(\Lambda _\Gamma \) associated with such a subgroup \(\Gamma \), with respect to the spherical metric on the boundary of complex hyperbolic n-space, is equal to the growth exponent \(\delta _\Gamma \). For general \(\Gamma \) we establish (under rather mild hypotheses) a lower bound involving the dimension of the Patterson–Sullivan measure along boundaries of complex geodesics. Our main tool is a version of the celebrated Ledrappier–Young theorem.
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Dufloux, L. Hausdorff dimension of limit sets. Geom Dedicata 191, 1–35 (2017). https://doi.org/10.1007/s10711-017-0240-2
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DOI: https://doi.org/10.1007/s10711-017-0240-2