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arXiv · 2610.09741

Intrinsic Hutchinson measures and KMS states for iterated function systems with large overlaps

Michael Mampusti·Alexander Mundey·Nicholas Seaton
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Abstract

We study iterated function systems with large overlaps via the Kajiwara-Watatani C*-algebra and its KMS states. Our main contributions are threefold. First, we introduce Markov partitions for iterated function systems and give an algorithm that constructs a finite Markov partition whenever one exists. Second, for contractive systems admitting a finite Markov partition, we construct an intrinsic analogue of the Hutchinson measure that is independent of any labelling or weighting of the maps. It is the unique Borel probability measure satisfying a self-similar integral equation dictated by the set-valued dynamics of the system, and it recovers the Hutchinson measure with uniform weights when the system satisfies the open set condition. Finally, we give a complete classification of KMS states for the gauge action on the Kajiwara-Watatani algebra of every such system. The critical inverse temperature is the exponential growth rate of the intrinsic orbits, which can be strictly smaller than the natural logarithm of the number of maps, and the unique KMS state at this temperature is given by our intrinsic Hutchinson measure. These systems include many with large overlaps not covered by the results of Izumi-Kajiwara-Watatani.

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Michael Mampusti, Alexander Mundey, Nicholas Seaton. 2026-10-07. Intrinsic Hutchinson measures and KMS states for iterated function systems with large overlaps. https://arxiv.org/abs/2610.09741

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