Authors: Mikhail Khristoforov Victor Kleptsyn Michele Triestino
Publish Date: 2016/06/01
Volume: 345, Issue: 1, Pages: 1-76
Abstract
This paper is inspired by the problem of understanding in a mathematical sense the Liouville quantum gravity on surfaces Here we show how to define a stationary random metric on selfsimilar spaces which are the limit of nice finite graphs these are the socalled hierarchical graphs They possess a welldefined level structure and any level is built using a simple recursion Stopping the construction at any finite level we have a discrete random metric space when we set the edges to have random length using a multiplicative cascade with fixed law m We introduce a tool the cutoff process by means of which one finds that renormalizing the sequence of metrics by an exponential factor they converge in law to a nontrivial metric on the limit space Such limit law is stationary in the sense that glueing together a certain number of copies of the random limit space according to the combinatorics of the brick graph the obtained random metric has the same law when rescaled by a random factor of law m In other words the stationary random metric is the solution of a distributional equation When the measure m has continuous positive density on mathbfR + the stationary law is unique up to rescaling and any other distribution tends to a rescaled stationary law under the iterations of the hierarchical transformation We also investigate topological and geometric properties of the random space when m is lognormal detecting a phase transition influenced by the branching random walk associated to the multiplicative cascade
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