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arXiv · 2110.13174

Operator product expansion coefficients from the nonperturbative functional renormalization group

Félix Rose·Carlo Pagani·Nicolas Dupuis
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Abstract

Using the nonperturbative functional renormalization group (FRG) within the Blaizot-M\'endez-Galain-Wschebor approximation, we compute the operator product expansion (OPE) coefficient $c_{112}$ associated with the operators $\mathcal{O}_1\sim\varphi$ and $\mathcal{O}_2\sim\varphi^2$ in the three-dimensional $\mathrm{O}(N)$ universality class and in the Ising universality class ($N=1$) in dimensions $2 \leq d \leq 4$. When available, exact results and estimates from the conformal bootstrap and Monte-Carlo simulations compare extremely well to our results, while FRG is able to provide values across the whole range of $d$ and $N$ considered.

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Félix Rose, Carlo Pagani, Nicolas Dupuis. 2021-10-25. Operator product expansion coefficients from the nonperturbative functional renormalization group. https://doi.org/10.1103/physrevd.105.065020

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