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Probing new physics in the top sector using quantum information

Rafael Aoude1,*, Hannah Banks2,†, Chris D. White3,‡, and Martin J. White4,§

  • 1Higgs Centre for Theoretical Physics, School of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3JZ, Scotland, United Kingdom
  • 2DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, United Kingdom
  • 3Centre for Theoretical Physics, School of Physical and Chemical Sciences, Queen Mary University of London, 327 Mile End Road, London E1 4NS, United Kingdom
  • 4ARC Centre of Excellence for Dark Matter Particle Physics & CSSM, Department of Physics, University of Adelaide, Adelaide, South Australia 5005, Australia

  • *Contact author: rafael.aoude@ed.ac.uk
  • †Contact author: hannah.banks@nyu.edu
  • ‡Contact author: christopher.white@qmul.ac.uk
  • §Contact author: martin.white@adelaide.edu.au
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Phys. Rev. D 113, 115066 – Published 30 June, 2026

DOI: https://doi.org/10.1103/c9yb-81kv

Abstract

Recent studies have shown that quantitative concepts from quantum information theory can play a role in analyzing collider physics, including elucidating new physics. In this paper, we study various quantum information measures including magic, trace distance, and fidelity distance, in generic new physics scenarios modeled by the standard model effective field theory. We argue that such measures can indeed show up differences with respect to the pure standard model, and we compare our results with similar findings for the concurrence discussed previously in the literature. We examine the relative sensitivity of different measures to new physics in two-dimensional bins of the top pair invariant mass and scattering angle, finding that the concurrence, magic, and trace distance each emerge as the best measure in at least some regions of the phase space. This highlights the importance of exploring multiple quantum information measures in the hunt for beyond the standard model physics.

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Phys. Rev. D 113, 115066– Published 30 June, 2026
  • Received 24 September 2025
  • Accepted 4 June 2026
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