Computable-modulus conjecture for the conformal-radius function

Let ff be the 11-periodic continuous function

f(θ)=Φ(θ)+logr(θ).f(\theta)=\Phi(\theta)+\log r(\theta).

A computable modulus of continuity for ff is a computable function μ:NN\mu:\mathbb{N}\to\mathbb{N} such that

f(θ1)f(θ2)<2nwheneverθ1θ2<2μ(n).|f(\theta_1)-f(\theta_2)|<2^{-n}\quad\text{whenever}\quad |\theta_1-\theta_2|<2^{-\mu(n)}.

Computable-modulus conjecture. The function ff has a computable modulus of continuity.

This conjecture would provide the quantitative continuity needed to show that the explicitly constructed parameter θ\theta, whose Julia set is non-computable, is nevertheless computable in polynomial time. No restriction is imposed on the growth rate of μ\mu beyond computability; the source gives no resolution of the conjecture.

Sources & referencesView supporting material

Primary source

Mark Braverman and Michael Yampolsky, “Constructing Non-Computable Julia Sets”, arXiv:math/0604371 (2006).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.