An extension of fractal Euler number via persistent homology

Kosuke Nishijima

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arXiv · 2605.22049

An extension of fractal Euler number via persistent homology

Kosuke Nishijima

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Abstract

In the context of geometric measure theory, Llorente-Winter introduced the (average) fractal Euler number as a notion of the Euler characteristic for fractals embedded in Euclidean space. However, the class of fractals to which it is applicable remains very limited. In the present paper, we modify this notion by applying perspectives of persistent homology and partly the theory of magnitude, which have recently come from applied topology and category theory. We then demonstrate concrete calculation of our average ph-fractal Euler number for some classically well-known fractals, especially the Cantor dust and Menger sponge which are excluded from Llorente-Winter's approach.

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Kosuke Nishijima. 2026-05-21. An extension of fractal Euler number via persistent homology. https://arxiv.org/abs/2605.22049

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