Taming the dark photon production via a non-minimal coupling to gravity

Key Points

• The absence of growth in models under explicit gauge invariance suggests significant theoretical limits.
• Significant growth was observed at large momenta in dark photons under non-minimal couplings to gravity.
• Utilizing non-minimal coupling, potential ghost instabilities can be avoided in gauge invariant frameworks.
• The findings indicate a path toward more robust quantum gravity theories with fewer theoretical uncertainties.