The return of Palatini inflationary attractors: Universal mapping of observables — E8 Intelligence Research

We study single-field slow-roll inflation in the context of Palatini gravity for the class of non-minimally coupled $ξ$-attractors, i.e.,\ models where the same function $f(φ)$ fixes both the non-minimal coupling, $1+ξf(φ)$, and the inflationary potential, $V(φ) = V_0 f(φ)^2$. As is well-known, for an arbitrary $f(φ)$, the number of $e$-folds is, at leading order, independent of $ξ$. Thanks to this, we provide an immediate mapping between the observables of the non-minimally coupled setup and those of the minimally coupled one. In the strong coupling limit, the tensor-to-scalar ratio is, as usual, suppressed, while the scalar spectral index is shifted towards larger values, with the magnitude of the shift depending only on the tensor-to-scalar ratio associated with the original potential $V(φ)$. Source: http://arxiv.org/abs/2609.20622v1 (arXiv:2609.20622v1) Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com