A rooted network consists of a connected, locally finite graph $G$, equipped with edge conductances and a distinguished vertex $o$. A nonnegative function on the vertices of $G$ which vanishes at $o$, has Laplacian $1$ at $o$, and is harmonic at all other vertices is called a potential. We prove that every infinite recurrent rooted network admits a potential tending to infinity. This is an analogue of classical theorems due to Evans and Nakai in the settings of Euclidean domains and Riemannian surfaces.
Un réseau enraciné est un graphe $G$ localement fini et connexe, doté de conductances sur les arêtes et d’un sommet distingué $o$. Un potentiel est une fonction sur les sommets de $G$ qui est positive, s’annule en $o$, a un laplacien $1$ en $o$ et est harmonique en tous les autres sommets. Nous prouvons que tout réseau enraciné, récurrent et infini admet un potentiel tendant vers l’infini. Il s’agit d’un analogue de théorèmes classiques de Evans et Nakai dans le cadre des domaines euclidiens et des surfaces riemanniennes.
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Asaf Nachmias 1; Yuval Peres 2

@article{CRMATH_2025__363_G8_793_0, author = {Asaf Nachmias and Yuval Peres}, title = {Every recurrent network has a potential tending to infinity}, journal = {Comptes Rendus. Math\'ematique}, pages = {793--798}, publisher = {Acad\'emie des sciences, Paris}, volume = {363}, year = {2025}, doi = {10.5802/crmath.758}, language = {en}, }
Asaf Nachmias; Yuval Peres. Every recurrent network has a potential tending to infinity. Comptes Rendus. Mathématique, Volume 363 (2025), pp. 793-798. doi : 10.5802/crmath.758. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.5802/crmath.758/
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