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arXiv · 1506.00961

Fourier dimension of random images

Fredrik Ekström
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Abstract

Given a compact set of real numbers, a random $C^{m + α}$-diffeomorphism is constructed such that the image of any measure concentrated on the set and satisfying a certain condition involving a real number $s$, almost surely has Fourier dimension greater than or equal to $s / (m + α)$. This is used to show that every Borel subset of the real numbers of Hausdorff dimension $s$ is $C^{m + α}$-equivalent to a set of Fourier dimension greater than or equal to $s / (m + α)$. In particular every Borel set is diffeomorphic to a Salem set, and the Fourier dimension is not invariant under $C^m$-diffeomorphisms for any $m$.

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Fredrik Ekström. 2016-02-07. Fourier dimension of random images. https://doi.org/10.1007/s11512-016-0237-3

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