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arXiv · 2205.07114

Regularity for free multiplicative convolution on the unit circle

Serban T. Belinschi·Hari Bercovici·Ching-Wei Ho
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Abstract

It is shown that the free multiplicative convolution of two nondegenerate probability measures on the unit circle has no continuous singular part relative to arclength measure. Analogous results have long been known for free additive convolutions on the line and free multiplicative convolution on the positive half-line.

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Serban T. Belinschi, Hari Bercovici, Ching-Wei Ho. 2022-05-14. Regularity for free multiplicative convolution on the unit circle. https://doi.org/10.2140/pjm.2023.322.243

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