Dimensions and dimension spectra of Non-autonomous iterated function systems

Junjie Miao; Tianrui Wang

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arXiv · 2508.20632

Dimensions and dimension spectra of Non-autonomous iterated function systems

Junjie Miao·Tianrui Wang

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Abstract

Non-autonomous iterated function systems are a generalization of iterated function systems. If the contractions in the system are conformal mappings, it is called a non-autonomous conformal iterated function system, and its attractor is called a non-autonomous conformal set. In this paper, we study intermediate dimension spectra of non-autonomous conformal sets which provide a unifying framework for Hausdorff and box-counting dimensions. First, we obtain the intermediate dimension spectra formula of non-autonomous conformal sets by using upper and lower topological pressures. As a consequence, we obtain simplified forms of their Hausdorff, packing and box dimensions. Finally, we explore the Hausdorff dimensions of the non-autonomous infinite conformal iterated function systems which consists of countably many conformal mappings at each level, and we provide the Hausdorff dimension formula under certain conditions.

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Junjie Miao, Tianrui Wang. 2025-08-28. Dimensions and dimension spectra of Non-autonomous iterated function systems. https://arxiv.org/abs/2508.20632

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