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arXiv · 2509.20740

Massless S-matrix Bootstraps and RG Flows

Changrim Ahn
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Abstract

We find complete solutions of S-matrix bootstrap equations for the scatterings of massless particles in (1+1) dimensions with A_n symmetries. We show that only three types (minimal, diagonal, and saturated cases) of these S-matrices can generate RG flows that lead to UV-complete theories, and other RG flows predicted in [11] are inconsistent with the bootstrap equations. Using these S-matrices, we derived the TBA equations and corresponding Y-systems that generate the RG flows between the IR and UV CFTs.

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Changrim Ahn. 2025-09-25. Massless S-matrix Bootstraps and RG Flows. https://arxiv.org/abs/2509.20740

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