“…It is well-known that isoperimetric inequalities are of interest in applied and pure mathematics [22,48]. The Cheeger isoperimetric inequality is related with many conformal invariants in Riemannian manifolds and graphs, namely the exponent of convergence, the bottom of the spectrum of the Laplace-Beltrami operator, Poincaré-Sobolev inequalities, and the Hausdorff dimensions of the sets of both escaping and bounded geodesics in negatively curved surfaces [4,13], [18, p. 228], [23,[27][28][29][30][31]43,46], [52, p. 333]. Isoperimetric inequality is also closely related to Ancona's project on the space of positive harmonic functions of Gromov-hyperbolic graphs and manifolds [7][8][9].…”