Abstract
In this paper, we compute multiparticle form factors of local operators in 2d ϕ4 theory using a recently proposed method [1] for efficiently implementing the LSZ prescription with Hamiltonian Truncation methods, and we adopt Lightcone Conformal Truncation (LCT) in particular for our calculations. We perform various checks of our results at weak and strong coupling, and elucidate the parametric behavior of truncation errors. This opens up the possibility to compute S-matrix in various strongly coupled models using the LSZ method in LCT.
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Acknowledgments
We thank Jed Thompson, Ami Katz, and Matthew Walters for many helpful discussions, and comments on a draft. ALF is supported by the US Department of Energy Office of Science under Award Number DE-SC0015845, and the Simons Collaboration on the Non- Perturbative Bootstrap. ALF thanks the Aspen Center of Physics for hospitality as this work was completed.
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Fitzpatrick, A.L., Mei, Z. LSZ in action: extracting form factors from correlators nonperturbatively in 2d ϕ4 theory. J. High Energ. Phys. 2024, 154 (2024). https://doi.org/10.1007/JHEP03(2024)154
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DOI: https://doi.org/10.1007/JHEP03(2024)154