Gauge Theory Bootstrap

We propose the gauge theory bootstrap, a method to compute the pion 𝑆 matrix that describes the low-energy physics of the strong interaction and other similar gauge theories. The phase shifts of the 𝑆⁢0, 𝑃⁢1, and 𝑆⁢2 waves obtained are in good agreement with experimental results. The only numerical inputs are the quark mass 𝑚𝑞, the QCD scale ΛQCD, the pion mass 𝑚𝜋, and the pion decay constant 𝑓𝜋 without any other experimental data. We make use of the form-factor bootstrap recently proposed by Karateev, Kuhn, and Penedones together with a finite energy version of the Shifman-Veinshtein-Zakharov sum rules.