English

Symmetry-breaking inflation in non-minimal metric-affine gravity

General Relativity and Quantum Cosmology 2025-05-28 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology

Abstract

We study symmetry-breaking inflation within the framework of metric-affine gravity. By introducing a non-minimal coupling, β(ϕ)R~\beta(\phi)\tilde{\cal R}, between the Holst invariant and the inflaton, both small-field and large-field inflationary predictions can be brought into agreement with the latest observational constraints. Remarkably, even for sub-Planckian vacuum expectation values, appropriately chosen values of β(ϕ)\beta(\phi) enable viable inflation, a scenario previously considered unattainable.

Keywords

Cite

@article{arxiv.2412.17738,
  title  = {Symmetry-breaking inflation in non-minimal metric-affine gravity},
  author = {Ioannis D. Gialamas and Antonio Racioppi},
  journal= {arXiv preprint arXiv:2412.17738},
  year   = {2025}
}

Comments

19 pages, 10 figures, matches published version