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Nonperturbative anomalous thresholds

Miguel Correia1

Phys. Rev. D 110, 025012 – Published 16 July, 2024

DOI: https://doi.org/10.1103/PhysRevD.110.025012

Abstract

Feynman diagrams (notably the triangle diagram) involving heavy enough particles contain branch cuts on the physical sheet—anomalous thresholds—which, unlike normal thresholds and bound-state poles, do not correspond to any asymptotic n-particle state. “Who ordered that?” We show that anomalous thresholds arise as a consequence of established S-matrix principles and two reasonable assumptions: unitarity below the physical region and analyticity in the mass. We find explicit nonperturbative formulas for the anomalous threshold singularity and test them against the Coleman-Thun poles of the E8 integrable model.

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References (79)

  1. S. Mandelstam, Unitarity condition below physical thresholds in the normal and anomalous cases, Phys. Rev. Lett. 4, 84 (1960).
  2. D. Olive, Unitarity and the evaluation of discontinuities—II, Nuovo Cimento (1955–1965) 29, 326 (1963).
  3. D. I. Olive, Exploration of S-matrix theory, Phys. Rev. 135, B745 (1964).
  4. J. Boyling, Hermitian analyticity and extended unitarity in S-matrix theory, Nuovo Cimento (1955–1965) 33, 1356 (1964).
  5. R. J. Eden, P. V. Landshoff, D. I. Olive, and J. C. Polkinghorne, The Analytic S-Matrix (Cambridge University Press, Cambridge, England, 1966).
  6. A. Homrich, J. Penedones, J. Toledo, B. C. van Rees, and P. Vieira, The S-matrix bootstrap IV: Multiple amplitudes, J. High Energy Phys. 11 (2019) 076.
  7. D. Karateev, S. Kuhn, and J. Penedones, Bootstrapping massive quantum field theories, J. High Energy Phys. 07 (2020) 035.
  8. A. L. Guerrieri, A. Homrich, and P. Vieira, Dual S-matrix bootstrap. Part I. 2D theory, J. High Energy Phys. 11 (2020) 084.
  9. H. S. Hannesdottir and S. Mizera, What is the iϵ for the S-Matrix? (Springer, Cham, 2022).
  10. R. Karplus, C. M. Sommerfield, and E. H. Wichmann, Spectral representations in perturbation theory. I. Vertex function, Phys. Rev. 111, 1187 (1958).
  11. R. Karplus, C. M. Sommerfield, and E. H. Wichmann, Spectral representations in perturbation theory. II. Two-particle scattering, Phys. Rev. 114, 376 (1959).
  12. Y. Nambu, Dispersion relations for form factors, Nuovo Cimento (1955–1965) 9, 610 (1958).
  13. R. Cutkosky, Anomalous thresholds, Rev. Mod. Phys. 33, 448 (1961).
  14. A. Martin, Selected topics on analyticity in potential scattering, Nuovo Cimento 21, 157 (1961).
  15. G. Barton, Introduction to Dispersion Techniques in Field Theory, Lecture Notes and Supplements in Physics (W.A. Benjamin, New York, 1965).
  16. A. Zhiboedov, Notes on the Analytic S-Matrix, GGI Lectures on the Theory of Fundamental Interactions (2022), https://www.ggi.infn.it/ggilectures/ggilectures2022/img/Notes_on_S-matrix_theory.pdf.
  17. F.-K. Guo, C. Hanhart, Q. Wang, and Q. Zhao, Could the near-threshold XYZ states be simply kinematic effects?, Phys. Rev. D 91, 051504 (2015).
  18. A. P. Szczepaniak, Triangle singularities and XYZ quarkonium peaks, Phys. Lett. B 747, 410 (2015).
  19. X.-H. Liu, M. Oka, and Q. Zhao, Searching for observable effects induced by anomalous triangle singularities, Phys. Lett. B 753, 297 (2016).
  20. M. Mikhasenko, A triangle singularity and the LHCb pentaquarks, arXiv:1507.06552.
  21. F.-K. Guo, U. G. Meißner, J. Nieves, and Z. Yang, Remarks on the Pc structures and triangle singularities, Eur. Phys. J. A 52, 318 (2016).
  22. M. Bayar, F. Aceti, F.-K. Guo, and E. Oset, A discussion on triangle singularities in the ΛbJ/ψKp reaction, Phys. Rev. D 94, 074039 (2016).
  23. F.-K. Guo, X.-H. Liu, and S. Sakai, Threshold cusps and triangle singularities in hadronic reactions, Prog. Part. Nucl. Phys. 112, 103757 (2020).
  24. M. Mikhasenko, B. Ketzer, and A. Sarantsev, Nature of the a1(1420), Phys. Rev. D 91, 094015 (2015).
  25. F. Aceti, L. R. Dai, and E. Oset, a1(1420) peak as the πf0(980) decay mode of the a1(1260), Phys. Rev. D 94, 096015 (2016).
  26. S. Mandelstam, Analytic properties of transition amplitudes in perturbation theory, Phys. Rev. 115, 1741 (1959).
  27. R. J. Eden, P. V. Landshoff, J. C. Polkinghorne, and J. C. Taylor, Ac nodes and cusps on Landau curves, J. Math. Phys. (N.Y.) 2, 656 (1961).
  28. M. Correia, A. Sever, and A. Zhiboedov, Probing multi-particle unitarity with the Landau equations, SciPost Phys. 13, 062 (2022).
  29. M. F. Paulos, J. Penedones, J. Toledo, B. C. van Rees, and P. Vieira, The S-matrix bootstrap II: Two dimensional amplitudes, J. High Energy Phys. 11 (2017) 143.
  30. N. Doroud and J. Elias Miró, S-matrix bootstrap for resonances, J. High Energy Phys. 09 (2018) 052.
  31. M. F. Paulos, J. Penedones, J. Toledo, B. C. van Rees, and P. Vieira, The S-matrix bootstrap. Part III: Higher dimensional amplitudes, J. High Energy Phys. 12 (2019) 040.
  32. Y. He, A. Irrgang, and M. Kruczenski, A note on the S-matrix bootstrap for the 2d O(N) bosonic model, J. High Energy Phys. 11 (2018) 093.
  33. L. Córdova and P. Vieira, Adding flavour to the S-matrix bootstrap, J. High Energy Phys. 12 (2018) 063.
  34. A. L. Guerrieri, J. Penedones, and P. Vieira, Bootstrapping QCD using pion scattering amplitudes, Phys. Rev. Lett. 122, 241604 (2019).
  35. J. Elias Miró, A. L. Guerrieri, A. Hebbar, J. a. Penedones, and P. Vieira, Flux Tube S-matrix bootstrap, Phys. Rev. Lett. 123, 221602 (2019).
  36. M. F. Paulos and Z. Zheng, Bounding scattering of charged particles in 1+1 dimensions, J. High Energy Phys. 05 (2020) 145.
  37. C. Bercini, M. Fabri, A. Homrich, and P. Vieira, S-matrix bootstrap: Supersymmetry, Z2, and Z4 symmetry, Phys. Rev. D 101, 045022 (2020).
  38. L. Córdova, Y. He, M. Kruczenski, and P. Vieira, The O(N) S-matrix Monolith, J. High Energy Phys. 04 (2020) 142.
  39. M. Kruczenski and H. Murali, The R-matrix bootstrap for the 2d O(N) bosonic model with a boundary, J. High Energy Phys. 04 (2021) 097.
  40. A. L. Guerrieri, J. Penedones, and P. Vieira, S-matrix bootstrap for effective field theories: Massless pions, J. High Energy Phys. 06 (2021) 088.
  41. A. Hebbar, D. Karateev, and J. Penedones, Spinning S-matrix bootstrap in 4d, J. High Energy Phys. 01 (2022) 060.
  42. A. Sinha and A. Zahed, Crossing symmetric dispersion relations in quantum field theories, Phys. Rev. Lett. 126, 181601 (2021).
  43. A. Guerrieri, J. Penedones, and P. Vieira, Where is string theory in the space of scattering amplitudes?, Phys. Rev. Lett. 127, 081601 (2021).
  44. P. Tourkine and A. Zhiboedov, Scattering from production in 2d, J. High Energy Phys. 07 (2021) 228.
  45. D. Karateev, J. Marucha, J. a. Penedones, and B. Sahoo, Bootstrapping the a-anomaly in 4d QFTs, J. High Energy Phys. 12 (2022) 136.
  46. J. Elias Miró and A. Guerrieri, Dual EFT bootstrap: QCD flux tubes, J. High Energy Phys. 10 (2021) 126.
  47. Y. He and M. Kruczenski, S-matrix bootstrap in 3+1 dimensions: Regularization and dual convex problem, J. High Energy Phys. 08 (2021) 125.
  48. A. Guerrieri and A. Sever, Rigorous bounds on the analytic S matrix, Phys. Rev. Lett. 127, 251601 (2021).
  49. S. D. Chowdhury, K. Ghosh, P. Haldar, P. Raman, and A. Sinha, Crossing symmetric spinning S-matrix bootstrap: EFT bounds, SciPost Phys. 13, 051 (2022).
  50. H. Chen, A. L. Fitzpatrick, and D. Karateev, Nonperturbative bounds on scattering of massive scalar particles in d2, J. High Energy Phys. 12 (2022) 092.
  51. J. E. Miro, A. Guerrieri, and M. A. Gumus, Bridging positivity and S-matrix bootstrap bounds, J. High Energy Phys. 05 (2023) 001.
  52. A. Guerrieri, H. Murali, J. Penedones, and P. Vieira, Where is M-theory in the space of scattering amplitudes?, J. High Energy Phys. 06 (2023) 064.
  53. K. Häring, A. Hebbar, D. Karateev, M. Meineri, and J. a. Penedones, Bounds on photon scattering, arXiv:2211.05795.
  54. M. Correia, J. Penedones, and A. Vuignier, Injecting the UV into the bootstrap: Ising field theory, J. High Energy Phys. 08 (2023) 108.
  55. M. Kruczenski, J. Penedones, and B. C. van Rees, Snowmass White Paper: S-matrix bootstrap, arXiv:2203.02421.
  56. S. R. Coleman and H. J. Thun, On the prosaic origin of the double poles in the Sine-Gordon S matrix, Commun. Math. Phys. 61, 31 (1978).
  57. A. B. Zamolodchikov, Integrals of motion and S matrix of the (scaled) T=T(c) Ising model with magnetic field, Int. J. Mod. Phys. A 04, 4235 (1989).
  58. T. J. Hollowood and P. Mansfield, Rational conformal field theories at, and away from, criticality as Toda field theories, Phys. Lett. B 226, 73 (1989).
  59. G. Delfino, Integrable field theory and critical phenomena: The Ising model in a magnetic field, J. Phys. A 37, R45 (2004).
  60. R. Oehme, Continuation of scattering amplitudes and form factors through two-particle branch lines, Phys. Rev. 121, 1840 (1961).
  61. M. Correia, A. Sever, and A. Zhiboedov, An analytical toolkit for the S-matrix bootstrap, J. High Energy Phys. 03 (2021) 013.
  62. J. Boyling, Normal threshold behaviour in the presence of anomalous thresholds, Il Nuovo Cimento A (1971-1996) 45, 706 (1966).
  63. P. Goddard, Anomalous threshold singularities in S-matrix theory, Il Nuovo Cimento A (1965-1970) 59, 335 (1969).
  64. V. N. Gribov, Analytic properties of the partial wave amplitudes and the asymptotic behavior of the scattering amplitude, Sov. Phys. JETP 15, 873 (1962).
  65. J. R. Pelaez, From controversy to precision on the sigma meson: A review on the status of the non-ordinary f0(500) resonance, Phys. Rep. 658, 1 (2016).
  66. R. Blankenbecler and Y. Nambu, Anomalous thresholds in dispersion theory-I, Nuovo Cimento (1955–1965) 18, 595 (1960).
  67. R. Blankenbecler and L. F. Cook, Bound states and dispersion relations, Phys. Rev. 119, 1745 (1960).
  68. R. Blankenbecler, M. L. Goldberger, S. W. MacDowell, and S. B. Treiman, Singularities of scattering amplitudes on unphysical sheets and their interpretation, Phys. Rev. 123, 692 (1961).
  69. L. F. Cook and B. W. Lee, Unitarity and production amplitudes, Phys. Rev. 127, 283 (1962).
  70. J. S. Ball, W. R. Frazer, and M. Nauenberg, Scattering and production amplitudes with unstable particles, Phys. Rev. 128, 478 (1962).
  71. J. B. Bronzan and C. Kacser, Khuri-Treiman representation and perturbation theory, Phys. Rev. 132, 2703 (1963).
  72. I. J. R. Aitchison, Logarithmic singularities in processes with two final-state interactions, Phys. Rev. 133, B1257 (1964).
  73. V. Gribov, Analytic properties of partial wave amplitudes and asymptotic behaviour of scattering amplitude, Nucl. Phys. 40, 107 (1963).
  74. J. M. Greben and L. P. Kok, Anomalous thresholds in an ND approach to nuclear reactions, Phys. Rev. C 13, 489 (1976).
  75. M. Hoferichter, G. Colangelo, M. Procura, and P. Stoffer, Virtual photon-photon scattering, Int. J. Mod. Phys. Conf. Ser. 35, 1460400 (2014).
  76. G. Colangelo, M. Hoferichter, M. Procura, and P. Stoffer, Dispersive approach to hadronic light-by-light scattering, J. High Energy Phys. 09 (2014) 091.
  77. L. D. Landau, On analytic properties of vertex parts in quantum field theory, Nucl. Phys. 13, 181 (1959).
  78. B. Henning, H. Murayama, F. Riva, J. O. Thompson, and M. T. Walters, Towards a nonperturbative construction of the S-matrix, J. High Energy Phys. 05 (2023) 197.
  79. A. L. Fitzpatrick, E. Katz, and Y. Xin, Lightcone Hamiltonian for Ising field theory I: T<T_c, arXiv:2311.16290.

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