A comparison of Euclidean and Heisenberg Hausdorff measures

We prove some geometric properties of sets in the first Heisenberg group whose Heisenberg Hausdorff dimension is the minimal or maximal possible in relation to their Euclidean one and the corresponding Hausdorff measures are positive and finite. In the firs, case we show that these sets must be in a sense horizontal and in the second case vertical. We show the sharpness of our results with some examples.Peer reviewe

The effect of projections on dimension in the Heisenberg group

We prove analogs of classical almost sure dimension theorems for Euclidean projection mappings in the first Heisenberg group, equipped with a sub-Riemannian metric