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  • Open Access

Dilaton effective field theory across the conformal edge

Thomas Appelquist1,*, James Ingoldby2,†, and Maurizio Piai3,4,‡

  • *Contact author: thomas.appelquist@yale.edu
  • †Contact author: james.a.ingoldby@durham.ac.uk
  • ‡Contact author: m.piai@swansea.ac.uk
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Phys. Rev. D 114, 014518 – Published 23 July, 2026

DOI: https://doi.org/10.1103/1gcc-v4zs

Abstract

Dilaton effective field theory can be employed to analyze lattice data in gauge theories that lie in close proximity of the lower edge of the conformal window. Under special conditions, we show that it can be used as a diagnostic tool to distinguish near-conformal, yet confining, theories from infrared conformal ones. We demonstrate this efficacy by analyzing two sets of lattice measurements taken from the literature. For the SU(3) theory coupled to Nf=8 Dirac fermions transforming in the fundamental representation, our analysis favors confinement. For the SU(2) theory with Nf=1 adjoint fermion, our fits favor infrared conformal behavior. We discuss future lattice measurements, and analysis refinements, that can further test this framework.

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Phys. Rev. D 114, 014518– Published 23 July, 2026
  • Received 20 February 2026
  • Accepted 25 June 2026
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