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Do orbits from different repelling fixed points fall into the same category for commuting maps

Determine whether, for two commuting holomorphic self-maps q and y of the unit disc D, any two forward orbits under q that start at two different boundary regular repelling fixed points of y necessarily exhibit the same qualitative behavior (i.e., fall into the same category of asymptotic behavior for such orbits, such as converging in finite time to a common fixed point distinct from the Denjoy–Wolff point or forming sequences of repelling fixed points tending to the Denjoy–Wolff point).

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Background

The paper studies when commutativity with a single element of a one-parameter semigroup extends to all its fractional iterates and analyzes the behavior on petals. In their parabolic setting, the authors prove structural results (Theorems 1.8 and 1.9) describing how a univalent non-elliptic self-map q interacts with the petals of a semigroup (V_t), including the fate of orbits starting from repelling fixed points of V_1.

They contrast this with the general setting of two commuting holomorphic self-maps q, y ∈ Hol(D), as investigated by Bracci [8], where richer dynamical behaviors may occur (e.g., repelling cycles of y). In this broader context, the authors explicitly note an unresolved issue: whether orbits of q starting at different repelling fixed points of y must share the same qualitative type. This remains unclear outside the specific framework treated in the paper.

References

Moreover, in contrast to the context of Theorem 1.9, it is not clear in general whether any two orbits starting from different repelling fixed points of y necessarily fall into the same category.

Criteria for extension of commutativity to fractional iterates of holomorphic self-maps in the unit disc (2406.00847 - Contreras et al., 2 Jun 2024) in Remark 1.10, Section 1 (Introduction and main results)