English

Mutated hilltop inflation revisited

General Relativity and Quantum Cosmology 2018-05-15 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

In this work we re-investigate pros and cons of mutated hilltop inflation. Applying Hamilton-Jacobi formalism we solve inflationary dynamics and find that inflation goes on along the W1{\cal W}_{-1} branch of the Lambert function. Depending on the model parameter mutated hilltop model renders two types of inflationary solutions: one corresponds to small inflaton excursion during observable inflation and the other describes large field inflation. The inflationary observables from curvature perturbation are in tune with the current data for a wide range of the model parameter. The small field branch predicts negligible amount of tensor to scalar ratio rO(104)r\sim \mathcal{O}(10^{-4}), while the large field sector is capable of generating high amplitude for tensor perturbations, rO(101)r\sim \mathcal{O}(10^{-1}). Also, the spectral index is almost independent of the model parameter along with a very small negative amount of scalar running. Finally we find that the mutated hilltop inflation closely resembles the α\alpha-attractor class of inflationary models in the limit of αϕ1\alpha\phi\gg 1.

Keywords

Cite

@article{arxiv.1711.00833,
  title  = {Mutated hilltop inflation revisited},
  author = {Barun Kumar Pal},
  journal= {arXiv preprint arXiv:1711.00833},
  year   = {2018}
}

Comments

17 pages, 13 figures. Accepted for publication in EPJC

R2 v1 2026-06-22T22:34:17.912Z