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تسجيل مستخدم جديدDirichlet-Poincar{e} profiles of graphs and groups
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تأليف
David Hume
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We define Poincar{e} profiles of Dirichlet type for graphs of bounded degree, in analogy with the Poincar{e} profiles (of Neumann type) defined in [HMT19]. The obvious first definition yields nothing of interest, but an alternative definition yields a spectrum of profiles which are quasi-isometry invariants and monotone with respect to subgroup inclusion. Moreover, in the extremal cases $p=1$ and $p=infty$, they detect the Fo lner function and the growth function respectively.
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