Year: 2026
Type: preprint
Abstract: 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, $V(ϕ) = M^4 f(ϕ)^2$. 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: arXiv (Cornell University)
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7213604043