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An application of a local version of Chang's theorem

Tom Sanders
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Abstract

We prove a theorem claimed in math.CA/0605519 which asserts that if A is a subset of a compact abelian group G with density of a particular (natural, although technical) form then the A(G)-norm (that is the sum of the absolute values of the Fourier transform) of the characteristic function of A cannot be too small.

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Tom Sanders. 2006-07-26. An application of a local version of Chang's theorem. https://arxiv.org/abs/math/0607668

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