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arXiv · 2007.07914

The Lorentzian inversion formula and the spectrum of the 3d O(2) CFT

Junyu Liu·David Meltzer·David Poland·David Simmons-Duffin
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Abstract

We study the spectrum and OPE coefficients of the three-dimensional critical O(2) model, using four-point functions of the leading scalars with charges 0, 1, and 2 ($s$, $\phi$, and $t$). We obtain numerical predictions for low-twist OPE data in several charge sectors using the extremal functional method. We compare the results to analytical estimates using the Lorentzian inversion formula and a small amount of numerical input. We find agreement between the analytic and numerical predictions. We also give evidence that certain scalar operators lie on double-twist Regge trajectories and obtain estimates for the leading Regge intercepts of the O(2) model.

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Junyu Liu, David Meltzer, David Poland, David Simmons-Duffin. 2020-07-15. The Lorentzian inversion formula and the spectrum of the 3d O(2) CFT. https://doi.org/10.1007/jhep09(2020)115

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