Quintessential Inflation in Light of ACT DR6
Sayantan Choudhury, Swapnil Kumar Singh, Satish Kumar Sahoo

TL;DR
This paper investigates a minimal quintessential inflation model with a runaway exponential potential, predicting precise inflationary observables and a detectable gravitational-wave background, linking early and late cosmic acceleration.
Contribution
It provides a highly predictive, single-field quintessential inflation model that tightly links inflationary parameters with late-time acceleration and forecasts a detectable gravitational-wave background.
Findings
Predicted spectral index n_s = 0.964241
Tensor-to-scalar ratio r = 7.48e-5 at N=60
Detectable blue-tilted gravitational-wave background for future interferometers
Abstract
We perform a precision investigation of smooth quintessential inflation in which a single canonical scalar field unifies the two known phases of cosmic acceleration. Using a CMB-normalized runaway exponential potential, we obtain sharply predictive inflationary observables: a red-tilted spectrum with and an exceptionally suppressed tensor-to-scalar ratio at , lying near the optimal region of current Planck+ACT constraints. Remarkably, all observable scales exit the horizon within an extremely narrow field interval , tightly linking early and late-time dynamics and reducing theoretical ambiguities. While inflationary tensors remain invisible to CMB B-mode surveys, the subsequent stiff epoch-an intrinsic hallmark of quintessential cosmology-imprints a blue-tilted stochastic gravitational-wave background…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsCosmology and Gravitation Theories · Noncommutative and Quantum Gravity Theories · Pulsars and Gravitational Waves Research
