English

Exact inflationary solutions in exponential gravity

General Relativity and Quantum Cosmology 2019-03-18 v2 High Energy Physics - Theory

Abstract

We consider a modified gravity model of the form f(R,ϕ)=Reh(ϕ)R f(R,\phi)=R e^{h(\phi)R} , where the strong gravity corrections are taken to all orders and ϕ\phi is a self-interacting massless scalar field. We show that the conformal transformation of this model to Einstein frame leads to non-canonical kinetic term and negates the advantage of the Einstein frame. We obtain exact solutions for the background in the Jordan frame without performing conformal transformations and show that the model leads to inflation with exit. We obtain scalar and tensor power-spectrum in Jordan frame and show that the model leads to red-tilt. We discuss the implications of the same in the light of cosmological observations.

Keywords

Cite

@article{arxiv.1706.10150,
  title  = {Exact inflationary solutions in exponential gravity},
  author = {Joseph P Johnson and Jose Mathew and S. Shankaranarayanan},
  journal= {arXiv preprint arXiv:1706.10150},
  year   = {2019}
}

Comments

17 pages, 4 figures, 2 tables

R2 v1 2026-06-22T20:34:27.611Z