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Random homeomorphisms and Fourier expansions - the pointwise behavior

Gady Kozma
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Abstract

Let phi be a Dubins-Freedman random homeomorphism on [0,1] derived from the base measure uniform on the vertical line x=1/2, and let f be a periodic function satisfying that |f(x)-f(0)| = o(1/log log log 1/x). Then the Fourier expansion of f composed with phi converges at 0 with probability 1. In the condition on f, o cannot be replaced by O. Also we deduce some 0-1 laws for this kind of problems.

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Gady Kozma. 2005-11-02. Random homeomorphisms and Fourier expansions - the pointwise behavior. https://arxiv.org/abs/math/0511036

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