Non-minimal coupling of the inflaton to the Holst invariant in metric-affine gravity induces quasi-pole kinetics that generate an exponential plateau potential and Starobinsky-equivalent predictions regardless of the bare potential.
The Palatini side of inflationary attractors
4 Pith papers cite this work. Polarity classification is still indexing.
4
Pith papers citing it
abstract
We perform an analysis of models of chaotic inflation where the inflaton field $\phi$ is coupled non-minimally to gravity via $\xi \phi^n g^{\mu\nu}R_{\mu\nu}(\Gamma), n>0$. We focus on the Palatini theory of gravity, i.e. the case where the assumptions of the General Relativity are relaxed (that of the connection being the Levi-Civita one) and the gravitational degrees of freedom are encoded not only in the metric but also the connection $\Gamma$, which is treated as an independent variable. We show that in this case the famous attractor behaviour of simple non-minimally coupled models of inflation is lost. Therefore the attractors are not universal but their existence depends on the underlying theory of gravity in a subtle way. We discuss what this means for chaotic models and their observational consequences.
citation-role summary
background 2
citation-polarity summary
verdicts
UNVERDICTED 4roles
background 2polarities
background 2representative citing papers
Combining periodic non-minimal couplings to the Nieh-Yan term and Ricci scalar in metric-affine gravity makes natural inflation viable for sub-Planckian periodicity scales.
New ξ-attractors with non-minimal coupling and non-canonical kinetics yield Einstein-frame exponential and polynomial potentials whose ns spans 1-2/N to 1-1/N and r can reach zero as ξ grows, fitting Planck, BICEP/Keck, ACT, SPT, and DESI data, plus a supergravity realization.
Multi-phase non-minimal inflation in metric and Palatini gravity predicts ns between 0.93 and 0.98, r up to 0.03 in metric but below 10^{-5} in Palatini, with non-thermal DM and leptogenesis viable for couplings in the 10^{-7} to 10^{-3} range.
citing papers explorer
-
Quasi-pole inflation in metric-affine gravity
Non-minimal coupling of the inflaton to the Holst invariant in metric-affine gravity induces quasi-pole kinetics that generate an exponential plateau potential and Starobinsky-equivalent predictions regardless of the bare potential.
-
Natural Metric-Affine Inflation: Reloaded
Combining periodic non-minimal couplings to the Nieh-Yan term and Ricci scalar in metric-affine gravity makes natural inflation viable for sub-Planckian periodicity scales.
-
New Exponential and Polynomial $\xi$-attractors
New ξ-attractors with non-minimal coupling and non-canonical kinetics yield Einstein-frame exponential and polynomial potentials whose ns spans 1-2/N to 1-1/N and r can reach zero as ξ grows, fitting Planck, BICEP/Keck, ACT, SPT, and DESI data, plus a supergravity realization.
-
Induced Multi-phase Inflation with Reheating: Leptogenesis and Dark Matter Production in Metric versus Palatini
Multi-phase non-minimal inflation in metric and Palatini gravity predicts ns between 0.93 and 0.98, r up to 0.03 in metric but below 10^{-5} in Palatini, with non-thermal DM and leptogenesis viable for couplings in the 10^{-7} to 10^{-3} range.