Wavelets and graph $C^*$-algebras

Carla Farsi; Elizabeth Gillaspy; Sooran Kang; Judith Packer

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arXiv · 1601.00061

Wavelets and graph $C^*$-algebras

Carla Farsi·Elizabeth Gillaspy·Sooran Kang·Judith Packer

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Abstract

Here we give an overview on the connection between wavelet theory and representation theory for graph $C^{\ast}$-algebras, including the higher-rank graph $C^*$-algebras of A. Kumjian and D. Pask. Many authors have studied different aspects of this connection over the last 20 years, and we begin this paper with a survey of the known results. We then discuss several new ways to generalize these results and obtain wavelets associated to representations of higher-rank graphs. In \cite{FGKP}, we introduced the "cubical wavelets" associated to a higher-rank graph. Here, we generalize this construction to build wavelets of arbitrary shapes. We also present a different but related construction of wavelets associated to a higher-rank graph, which we anticipate will have applications to traffic analysis on networks. Finally, we generalize the spectral graph wavelets of \cite{hammond} to higher-rank graphs, giving a third family of wavelets associated to higher-rank graphs.

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Carla Farsi, Elizabeth Gillaspy, Sooran Kang, Judith Packer. 2016-01-01. Wavelets and graph $C^*$-algebras. https://arxiv.org/abs/1601.00061

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