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arXiv · 2512.20295

Critical Temperature(s) of Sierpinski Carpet(s)

Riccardo Ben Alì Zinati·Giacomo Gori·Alessandro Codello
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Abstract

We present a key algorithmic improvement to the generalized combinatorial Feynman--Vdovichenko method for calculating the critical temperature of the Ising model on Sierpinski carpets $SC_k(a,b)$, originally introduced in arxiv:1505.02699. By reformulating the method in terms of purely real-valued transfer matrices, we substantially reduce their dimension. This optimization, together with modern computational resources, enables us to reach generation $k=10$ for the canonical $SC_k(3,1)$ carpet. Extrapolation from these data yields the most accurate estimate to date of the critical temperature $T_c^{(3,1)} = 1.4782927(26)$. We further extend the analysis to additional members of the $SC_k(a,b)$ family and report their corresponding critical temperatures.

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Riccardo Ben Alì Zinati, Giacomo Gori, Alessandro Codello. 2025-12-23. Critical Temperature(s) of Sierpinski Carpet(s). https://doi.org/10.1140/epjb%2Fs10051-026-01196-1

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