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arXiv · 0903.2166

The absolute continuity of the invariant measure of random iterated function systems with overlaps

Balazs Barany·Tomas Persson
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Abstract

We consider iterated function systems on the interval with random perturbation. Let $Y_\epsilon$ be uniformly distributed in $[1- \epsilon, 1 + \epsilon]$ and let $f_i \in C^{1+\alpha}$ be contractions with fixpoints $a_i$. We consider the iterated function system $\{Y_\epsilon f_i + a_i (1 - Y_\epsilon) \}_{i=1}^n$, were each of the maps are chosen with probability $p_i$. It is shown that the invariant density is in $L^2$ and the $L^2$-norm does not grow faster than $1/\sqrt{\epsilon}$, as $\epsilon$ vanishes.

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Balazs Barany, Tomas Persson. 2009-03-12. The absolute continuity of the invariant measure of random iterated function systems with overlaps. https://doi.org/10.4064/fm210-1-2

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