Henning, BrianMurayama, HitoshiRiva, FrancescoThompson, Jedidiah O.Walters, Matthew T.2023-07-032023-07-032023-07-032023-05-2510.1007/JHEP05(2023)197https://infoscience.epfl.ch/handle/20.500.14299/198776WOS:000995943200003We present a nonperturbative recipe for directly computing the S-matrix in strongly-coupled QFTs. The method makes use of spectral data obtained in a Hamiltonian framework and can be applied to a wide range of theories, including potentially QCD. We demonstrate the utility of this prescription in the specific example of the 2+1d O(N) model at large N, using energy eigenstates computed with Hamiltonian truncation to reproduce the full 2 -> 2 scattering amplitude for arbitrary (complex) center-of-mass energy.Physics, Particles & FieldsPhysicsnonperturbative effectsscattering amplitudesfield theories in lower dimensionstext::journal::journal article::research article