Abstract
We 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.
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Acknowledgments
It is a pleasure to thank Olivier Delouche, Savas Dimopoulos, Liam Fitzpatrick, Max Hansen, Denis Karateev, Ami Katz, Markus Luty, Sasha Monin, João Penedones, and Riccardo Rattazzi for valuable discussions. J.O.T. would like to thank the University of Geneva, CERN, EPFL, and Perimeter Institute for hospitality during the completion of this work. The work of B.H. is partially supported by the Swiss National Science Foundation under contract 200020-188671 and through the National Center of Competence in Research SwissMAP. The work of H.M. was supported by the Director, Office of Science, Office of High Energy Physics of the U.S. Department of Energy under the Contract No. DE-AC02-05CH11231, by the NSF grant PHY-1915314, by the JSPS Grant-in-Aid for Scientific Research JP20K03942, MEXT Grant-in-Aid for Transformative Research Areas (A) JP20H05850, JP20A203, and Hamamatsu Photonics, K.K. In addition H.M. is supported by the World Premier International Research Center Initiative (WPI) MEXT, Japan. This research was supported in part by Perimeter Institute for Theoretical Physics. Research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science. The work of F.R. and M.W. is supported by the Swiss National Science Foundation under grants no. 200021-205016 and PP00P2-206149.
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Henning, B., Murayama, H., Riva, F. et al. Towards a nonperturbative construction of the S-matrix. J. High Energ. Phys. 2023, 197 (2023). https://doi.org/10.1007/JHEP05(2023)197
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DOI: https://doi.org/10.1007/JHEP05(2023)197