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arXiv · 0709.2941

The p-harmonic boundary for finitely generated groups and the first reduced \ell_p-cohomology

Michael Puls
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Abstract

Let $p$ be a real number greater than one and let $G$ be a finitely generated, infinite group. In this paper we introduce the $p$-harmonic boundary of $G$. We then characterize the vanishing of the first reduced $\ell^p$-cohomology of $G$ in terms of the cardinality of this boundary. Some properties of $p$-harmonic boundaries that are preserved under rough isometries are also given. We also study the relationship between translation invariant linear functionals on a certain difference space of functions on $G$, the $p$-harmonic boundary of $G$ and the first reduced $\ell^p$-cohomology of $G$.

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Michael Puls. 2008-04-03. The p-harmonic boundary for finitely generated groups and the first reduced \ell_p-cohomology. https://arxiv.org/abs/0709.2941

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