English

Inflation with Non-Minimal Coupling: Metric vs. Palatini Formulations

High Energy Physics - Phenomenology 2008-11-26 v2 Astrophysics High Energy Physics - Theory

Abstract

We analyze non-minimally coupled scalar field theories in metric (second-order) and Palatini (first-order) formalisms in a comparative fashion. After contrasting them in a general setup, we specialize to inflation and find that the two formalisms differ in their predictions for various cosmological parameters. The main reason is that dependencies on the non-minimal coupling parameter are different in the two formalisms. For successful inflation, the Palatini approach prefers a much larger value for the non-minimal coupling parameter than the Metric approach. Unlike the Metric formalism, in Palatini, the inflaton stays well below the Planck scale whereby providing a natural inflationary epoch.

Keywords

Cite

@article{arxiv.0803.2664,
  title  = {Inflation with Non-Minimal Coupling: Metric vs. Palatini Formulations},
  author = {Florian Bauer and Durmus A. Demir},
  journal= {arXiv preprint arXiv:0803.2664},
  year   = {2008}
}

Comments

13 pages, reference added

R2 v1 2026-06-21T10:22:30.303Z