Related references
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Article
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Summary: In this paper, we revisit analytical methods for constraining the nonperturbative S-matrix of unitary, relativistic, gapped theories in spacetime dimensions of d >= 3. By assuming extended analyticity of the two-to-two scattering amplitude and using it together with elastic unitarity, we develop two natural expansions of the amplitude - the threshold (non-relativistic) expansion and the large spin expansion. These expansions are related by the Froissart-Gribov inversion formula and help constrain scattering at finite energy and spin in terms of low-energy parameters measured in experiments. Finally, we discuss how the modern numerical approach to the S-matrix bootstrap can be improved based on the results of our analysis.
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PHYSICAL REVIEW LETTERS
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Martin Kruczenski et al.
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Article
Physics, Particles & Fields
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(2021)
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Summary: In this study, the allowed space of S-matrices on the Adler zeros' plane is examined using a numerical S-matrix bootstrap program for pion scattering. The study focuses on two physical quantities, the averaged total scattering cross-section, and the averaged entanglement power. The emerging linearity in the leading Regge trajectory is found to be correlated with a reduction in these quantities, and two potentially viable regions with decent agreement with low energy scattering lengths are identified.
Article
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Simon Caron-Huot et al.
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(2021)
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Article
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