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arXiv · 2609.10667

Entanglement entropy in topological tensor networks

Vijay Balasubramanian·Charlie Cummings
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Abstract

We derive an entropy formula for recently proposed tensor network models which prepare diffeomorphism invariant states of topological quantum field theories with non-compact and/or continuous gauge groups. We show that our entropy formula generalizes the notion of ``topological entanglement entropy'' to incorporate the infinite number of particle-like excitations in such theories. When our networks are endowed with gauge group $\mathrm{SL}(2,\mathbb{R})$, we can interpret them as models of three-dimensional gravity with small Newton's constant and possibly non-invertible metrics.

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Vijay Balasubramanian, Charlie Cummings. 2026-09-09. Entanglement entropy in topological tensor networks. https://arxiv.org/abs/2609.10667

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