For a post-critically finite hyperbolic rational map f, we show that the Julia set Jf has Ahlfors-regular conformal dimension one if and only if f is a crochet map, i.e., there is an f-invariant graph G containing the post-critical set such that f|G has topological entropy zero. We use finite subdivision rules to obtain graph virtual endomorphisms, which are 1-dimensional simplifications of post-critically finite rational maps, and approximate the asymptotic conformal energies of the graph virtual endomorphisms to estimate the Ahlfors-regular conformal dimensions. In particular, we develop an idea of reducing finite subdivision rules and prove the monotonicity of asymptotic conformal energies under the decomposition of rational maps.
Submitted 27 September, 2022; originally announced September 2022.