Decrease of Fourier coefficients of stationary measures

Jialun Li

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arXiv · 1706.07184

Decrease of Fourier coefficients of stationary measures

Jialun Li

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Abstract

Let $\mu$ be a Borel probability measure on $\mathrm{SL}_2(\mathbb R)$ with a finite exponential moment, and assume that the subgroup $\Gamma_{\mu}$ generated by the support of $\mu$ is Zariski dense. Let $\nu$ be the unique $\mu-$stationary measure on $\mathbb P^1_{\mathbb R}$. We prove that the Fourier coefficients $\widehat{\nu}(k)$ of $\nu$ converge to $0$ as $|k|$ tends to infinity. Our proof relies on a generalized renewal theorem for the Cartan projection.

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Jialun Li. 2017-06-22. Decrease of Fourier coefficients of stationary measures. https://arxiv.org/abs/1706.07184

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