We prove that for typical rotation numbers 0 < θ < 1, the boundary of the Siegel disk of f θ (z) = e 2πiθ sin(z) centered at the origin is a Jordan curve which passes through exactly two critical points π/2 and −π/2.
Statement of the main resultLet 0 < θ < 1 be an irrational number and [a 1 , . . . , a n , . . .] be its continued fraction. We say that θ is of bounded type if sup{a n } < ∞. The set of bounded type irrational numbers has zero Lebesgue measure. The following theorem was proved in [10]. THEOREM 1.1. Let 0 < θ < 1 be a bounded type irrational number. Then the Siegel disk of e 2πiθ sin(z) centered at the origin is a quasi-disk with boundary containing exactly two critical points π/2 and −π/2. Theorem 1.1 was proved by performing quasi-conformal (qc) surgery on an appropriate premodel. In [7] the authors there proposed a surgery technique to construct Jordan Siegel disks with typical rotation numbers. This surgery technique was pioneered by Haissinsky, who used it to transform an attracting basin into a parabolic basin, and is now called transqc surgery. Petersen asked if Theorem 1.1 can be extended to the case of typical rotation numbers through trans-qc surgery. The main purpose of this paper is to prove the following theorem.MAIN THEOREM. For typical irrational numbers 0 < θ < 1, the Siegel disk of e 2πiθ sin(z) centered at the origin is a Jordan domain with boundary containing exactly two critical points π/2 and −π/2. Compared with qc surgery, the main difficulty in performing trans-qc surgery is to verify the integrability of certain degenerate Beltrami differentials. This often requires some delicate area estimates. In [7] the authors used Petersen puzzles developed in [6] to obtain the desired estimate for the Douady-Ghys Blaschke model. Such puzzle construction does not exist in constructing Siegel disks of entire functions. In fact it is not known if the