Gauge Theory Bootstrap: predicting pion dynamics from QCD

by Yifei He

Monday 1 Jun 2026, 14:00 → 15:00 Europe/Zurich

4/2-037 - TH meeting room (CERN)

I will present the Gauge Theory Bootstrap, a framework for computing the strongly coupled pion dynamics by constructing the most general scattering matrix, form factors and spectral densities consistent with physical principles and matched with perturbative QCD at high energies and with weakly coupled pions at low energies. This is a theoretical/numerical approach that uses as only input the pion mass m_\pi​, pion decay constant f_\pi​ and the QCD parameters N_c, N_f​, m_q and alpha_s​. Within this framework, we compute pion scattering phase shifts and form factors and extract the low-energy constants in the effective theory. In particular, we find the rho(770), f_2​(1270) and rho(1450) resonances in reasonable agreement with experimental data. Using these results, we discuss the thermodynamics of a pion gas including pair correlations of pions with same and opposite charge.
References:
[1] YH and Martin Kruczenski, Phys. Rev. Lett. 133, 191601 and Phys. Rev. D 110, 096001.
[2] YH and Martin Kruczenski, arXiv: 2403.10772.
[3] YH and Martin Kruczenski, arXiv: 2505.19332.