Nazarov, Fedor and Peres, Yuval and Shmerkin, Pablo
(2009)
*Convolutions of Cantor measures without resonance.*
[MIMS Preprint]

PDF
measure.pdf Download (249kB) |

## Abstract

Denote by $\mu_a$ the distribution of the random sum $(1-a) \sum_{j=0}^\infty \omega_j a^j$, where $P(\omega_j=0)=P(\omega_j=1)=1/2$ and all the choices are independent. For $0<a<1/2$, the measure $\mu_a$ is supported on $C_a$, the central Cantor set obtained by starting with the closed united interval, removing an open central interval of length $(1-2a)$, and iterating this process inductively on each of the remaining intervals. We investigate the convolutions $\mu_a * (\mu_b \circ S_\lambda^{-1})$, where $S_\lambda(x)=\lambda x$ is a rescaling map. We prove that if the ratio $\log b/\log a$ is irrational and $\lambda\neq 0$, then \[ D(\mu_a *(\mu_b\circ S_\lambda^{-1})) = \min(\dim_H(C_a)+\dim_H(C_b),1), \] where $D$ denotes any of correlation, Hausdorff or packing dimension of a measure. We also show that, perhaps surprisingly, for uncountably many values of $\lambda$ the convolution $\mu_{1/4} *(\mu_{1/3}\circ S_\lambda^{-1})$ is a singular measure, although $\dim_H(C_{1/4})+\dim_H(C_{1/3})>1$ and $\log (1/3) /\log (1/4)$ is irrational.

Item Type: | MIMS Preprint |
---|---|

Uncontrolled Keywords: | CICADA, correlation dimension, convolutions, self-similar measures, resonance |

Subjects: | MSC 2010, the AMS's Mathematics Subject Classification > 28 Measure and integration MSC 2010, the AMS's Mathematics Subject Classification > 42 Fourier analysis |

Depositing User: | Mr Pablo Shmerkin |

Date Deposited: | 14 Oct 2009 |

Last Modified: | 08 Nov 2017 18:18 |

URI: | http://eprints.maths.manchester.ac.uk/id/eprint/1333 |

### Actions (login required)

View Item |