Towards a formalism for pion-pion scattering from staggered lattice QCD

by Dean Valois (Granada University)

Tuesday 7 Jul 2026, 15:00 → 17:00 Europe/Berlin

Nußallee 14-16/0.023 (HISKP) - Lecture Hall (HISKP)

Scattering processes involving the strong interactions can be studied using lattice QCD via the Lüscher formalism. This approach relies on analyticity and unitarity of the S-matrix to relate finite-volume energies to infinite-volume scattering amplitudes. On the one hand, one of the most common lattice QCD actions relies on staggered fermions due to their high computational efficiency. On the other hand, simulations employing staggered fermions manifest highly non-trivial discretization artifacts that are not accounted for in the standard Lüscher formalism. Although these artifacts scale with the lattice spacing squared and thus disappear in the continuum, at non-zero lattice spacing, they hinder the applicability of the formalism to calculate scattering amplitudes. In this talk, we will start with an overview of the standard Lüscher formalism and then discuss how to deal with the challenges of extracting scattering amplitudes from staggered lattice QCD by generalizing the formalism to incorporate staggered lattice artifacts.