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Quantum gravity contributions to the gauge and Yukawa couplings in proper time flow

Gabriele Giacometti1,2,*, Kamila Kowalska3,†, Daniele Rizzo4,‡, Enrico Maria Sessolo3,§, and Dario Zappalà2,∥

  • *Contact author: gabriele.giacometti@phd.unict.it
  • †Contact author: kamila.kowalska@ncbj.gov.pl
  • ‡Contact author: daniele.rizzo@kbfi.ee
  • §Contact author: enrico.sessolo@ncbj.gov.pl
  • ∥Contact author: dario.zappala@ct.infn.it
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Phys. Rev. D 114, 016020 – Published 20 July, 2026

DOI: https://doi.org/10.1103/xyg5-lvq4

Abstract

We derive quantum gravity contributions to the beta functions of the gauge and Yukawa couplings of a matter theory using the Schwinger proper-time flow equation. Working in the Einstein-Hilbert truncation, we investigate the gauge fixing and regulator dependence of the corresponding renormalization group equations. We quantify the sensitivity of our results to unphysical parameters by evaluating the gravitational correction to the running matter couplings at the interactive fixed point of gravity and we compare our findings with existing determinations in alternative schemes. We finally confront the derived contributions with the typical size they should assume to generate observable low-scale predictions in the Standard Model and in several scenarios of new physics.

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Phys. Rev. D 114, 016020– Published 20 July, 2026
  • Received 14 April 2026
  • Accepted 21 May 2026
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