Every exponential group supports a positive harmonic function

Gideon Amir; Gady Kozma

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arXiv · 1711.00050

Every exponential group supports a positive harmonic function

Gideon Amir·Gady Kozma

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Abstract

We prove that all groups of exponential growth support non-constant positive harmonic functions. In fact, out results hold in the more general case of strongly connected, finitely supported Markov chains invariant under some transitive group of automorphisms for which the directed balls grow exponentially.

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Gideon Amir, Gady Kozma. 2017-10-31. Every exponential group supports a positive harmonic function. https://arxiv.org/abs/1711.00050

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