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arXiv · 2512.05197

Coarse-graining in time, emergent temperature in 2d CFT at large central charge

Gideon Vos
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Abstract

Using the monodromy method, a compact expression is obtained for the identity block contribution to the expectation value of two low-energy probe operators on a broad class of time-dependent heavy pure states in large-$c$ 2d CFTs. It will be shown that the size of the compact spatial dimension sets a coarse-graining time-scale above which the thermal two-point function naturally emerges. A phenomena will be highlighted where the information of the pure state appears to get projected down to a single conformal representation. We will see that this projection is corroborated by known conformal bootstrap results.

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Gideon Vos. 2025-12-04. Coarse-graining in time, emergent temperature in 2d CFT at large central charge. https://arxiv.org/abs/2512.05197

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