Quantized topological invariant of symmetry-projected Gibbs states

Weiguang Cao; Haruki Watanabe

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arXiv · 2608.04350

Quantized topological invariant of symmetry-projected Gibbs states

Weiguang Cao·Haruki Watanabe

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Abstract

We study Gibbs states projected onto the symmetric sector of contractible one-form symmetries. In a three-dimensional cluster-model interpolation, this projection stabilizes symmetry-protected topological and projected-paramagnetic phases, both sharply distinct from thermal disorder. A flux-twisted membrane invariant distinguishes these three phases by the values $-1,+1,0$, respectively. These values are exact on the endpoint, self-dual, zero-temperature, and infinite-temperature lines; elsewhere their quantization requires positive spatial-sheet, winding-line, and interface tensions. Quantum Monte Carlo supports the quantization through tension diagnostics and direct finite-size estimates.

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Weiguang Cao, Haruki Watanabe. 2026-08-05. Quantized topological invariant of symmetry-projected Gibbs states. https://arxiv.org/abs/2608.04350

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