Spectra of Bernoulli convolutions as multipliers in $L^p$ on the circle

dc.creatorSidorov, Nikita
dc.creatorSolomyak, Boris
dc.date2002-10-03
dc.date.accessioned2026-07-07T04:51:37Z
dc.date.available2026-07-07T04:51:37Z
dc.descriptionIt is shown that the closure of the set of Fourier coefficients of the Bernoulli convolution $μ_θ$ parameterized by a Pisot number $θ$, is countable. Combined with results of Salem and Sarnak, this proves that for every fixed $θ>1$ the spectrum of the convolution operator $f\mapsto μ_θ*f$ in $L^p(S^1)$ (where $S^1$ is the circle group) is countable and is the same for all $p\in(1,\infty)$, namely, $\bar{\{\hat{μ_θ}(n) : n\in\mathbb{Z}\}}$. Our result answers the question raised by P. Sarnak in \cite{Sar}. We also consider the sets $\bar{\{\hat{μ_θ}(rn) : n\in\mathbb{Z}\}}$ for $r>0$ which correspond to a linear change of variable for the measure. We show that such a set is still countable for all $r\in\Q(θ)$ but uncountable (a non-empty interval) for Lebesgue-a.e. $r>0$.
dc.description18 pages
dc.identifierhttps://arxiv.org/abs/math/0210053
dc.identifierhttp://arxiv.org/abs/math/0210053
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/65167
dc.subjectFunctional Analysis
dc.subjectDynamical Systems
dc.subjectNumber Theory
dc.subject47A10; 42A16; 11R06
dc.titleSpectra of Bernoulli convolutions as multipliers in $L^p$ on the circle
dc.typetext

Files

Collections