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arXiv · 2607.20632

An FBSDE Construction of the Sine-Gordon EQFT for $\beta^{2} < \frac{6}{7}\, 8\pi$ and Perturbative Renormalization in the Full Subcritical Regime

Sarah-Jean Meyer
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Abstract

We construct the sine-Gordon measure and its renormalized effective potential in finite volume up to the seventh threshold. The construction relies on a weak stochastic control problem, its associated weak FBSDE, and an analysis of the renormalization flow equation using a multipole Mayer expansion. The analysis is fully inductive, and we include a complete order-by-order analysis in the subcritical regime $\beta^{2}<8\pi$.

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Sarah-Jean Meyer. 2026-07-22. An FBSDE Construction of the Sine-Gordon EQFT for $\beta^{2} < \frac{6}{7}\, 8\pi$ and Perturbative Renormalization in the Full Subcritical Regime. https://arxiv.org/abs/2607.20632

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