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  • Letter
  • Open Access

Bounds on crossing symmetry

Sebastian Mizera*

  • Institute for Advanced Study, Einstein Drive, Princeton, New Jersey 08540, USA

  • *smizera@ias.edu
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Phys. Rev. D 103, L081701 – Published 12 April, 2021

DOI: https://doi.org/10.1103/PhysRevD.103.L081701

Abstract

Proposed in 1954 by Gell-Mann, Goldberger, and Thirring, crossing symmetry postulates that particles are indistinguishable from antiparticles traveling back in time. Its elusive proof amounts to demonstrating that scattering matrices in different crossing channels are boundary values of the same analytic function, as a consequence of physical axioms such as causality, locality, or unitarity. In this work we report on the progress in proving crossing symmetry on shell within the framework of perturbative quantum field theory. We derive bounds on internal masses above which scattering amplitudes are crossing symmetric to all loop orders. They are valid for four- and five-point processes, or to all multiplicity if one allows deformations of momenta into higher dimensions at intermediate steps.

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References (52)

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Outline

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Phys. Rev. D 103, L081701– Published 12 April, 2021
  • Received 23 January 2021
  • Accepted 11 March 2021
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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