2022/09/01 by De‐Jun Feng, Feng, De-Jun, Chiu-Hong Lo +3
Mathematics · Computer Science · #Mathematical Dynamics and Fractals #Advanced Topology and Set Theory #Computability, Logic, AI Algorithms
paper · pdf · doi:10.48550/arxiv.2209.00228
Let T1,…, Tm be a family of d× d invertible real matrices with ‖Ti‖<1/2 for 1≤ i≤ m. For \bf a=(a1,…, am)∈ \Bbb Rmd, let π\bf a: Σ=\1,…, m\\Bbb N→ \Bbb Rd denote the coding map associated with the affine IFS \Tix+ai\i=1m. We show that for every Borel probability measure μ on Σ, each of the following dimensions (lower and upper Hausdorff dimensions, lower and upper packing dimensions) of π\bf a_*μ is constant for \mathcal Lmd-a.e.~\bf a∈ \Bbb Rmd, where π\bf a_*μ stands for the push-forward of μ by π\bf a. In particular, we give a necessary and sufficient condition on μ so that π\bf a_*μ is exact dimensional for \mathcal Lmd-a.e.~\bf a∈ \Bbb Rmd. Moreover, for every analytic set E⊂ Σ, each of the Hausdorff, packing, lower and upper box-counting dimensions of π\bf a(E) is constant for \mathcal Lmd-a.e.~\bf a∈ \Bbb Rmd. Formal dimension formulas of these projected measures and sets are given. The Hausdorff dimensions of exceptional sets are estimated.