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arXiv · 2507.10656

Stabilizer R\'{e}nyi Entropy Encodes Fusion Rules of Topological Defects and Boundaries

Masahiro Hoshino·Yuto Ashida
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Abstract

We demonstrate that the stabilizer R\'{e}nyi entropy (SRE), a computable measure of quantum magic, can serve as an information-theoretic probe for universal properties associated with conformal defects in one-dimensional quantum critical systems. Using boundary conformal field theory, we show that open boundaries manifest as a universal logarithmic correction to the SRE, whereas topological defects yield a universal size-independent term. When multiple defects are present, we find that the universal terms in the SRE faithfully reflect the defect-fusion rules that define a noninvertible symmetry algebra. These analytical predictions are corroborated by numerical calculations of the Ising model, where boundaries and topological defects are described by Cardy states and Verlinde lines, respectively.

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Masahiro Hoshino, Yuto Ashida. 2025-07-14. Stabilizer R\'{e}nyi Entropy Encodes Fusion Rules of Topological Defects and Boundaries. https://doi.org/10.1103/1tyr-rlbb

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