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arXiv · 2605.14684

QCD axion from broken scale symmetry

Georgios K. Karananas·Mikhail Shaposhnikov
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Abstract

A consistent non-compact axion cosmology requires a non-periodic field, an effective field theory valid sufficiently above the inflationary scale, and a small non-QCD contribution to the potential that tilts the axionic vacuum landscape in order to trigger a timely domain-wall collapse. All conditions can be met by the dilaton -- the pseudo-Nambu-Goldstone boson of spontaneously broken approximate scale invariance.

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Georgios K. Karananas, Mikhail Shaposhnikov. 2026-05-14. QCD axion from broken scale symmetry. https://arxiv.org/abs/2605.14684

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