DIVERGENCE OF THE MOCK AND SCRAMBLED FOURIER SERIES ON FRACTAL MEASURES
Abbreviated Journal Title
Trans. Am. Math. Soc.
Fourier series; Dirichlet kernel; Hilbert space; fractal; selfsimilar; iterated function system; Hadamard matrix; ITERATED FUNCTION SYSTEMS; CANTOR MEASURES; CONVERGENCE; Mathematics
We study divergence properties of the Fourier series on Cantor-type fractal measures, also called the mock Fourier series. We show that in some cases the L-1-norm of the corresponding Dirichlet kernel grows exponentially fast, and therefore the Fourier series are not even pointwise convergent. We apply these results to the Lebesgue measure to show that a certain rearrangement of the exponential functions, with affine structure, which we call a scrambled Fourier series, have a corresponding Dirichlet kernel whose L-1-norm grows exponentially fast, which is much worse than the known logarithmic bound. The divergence properties are related to the Mahler measure of certain polynomials and to spectral properties of Ruelle operators.
Transactions of the American Mathematical Society
"DIVERGENCE OF THE MOCK AND SCRAMBLED FOURIER SERIES ON FRACTAL MEASURES" (2014). Faculty Bibliography 2010s. 5283.