English

Bouncing cosmology in a curved braneworld

General Relativity and Quantum Cosmology 2021-03-03 v2

Abstract

We explore the possibility of a non-singular bounce in our universe from a warped braneworld scenario with dynamical branes and a non-zero brane cosmological constant. Such models naturally incorporate a scalar sector known as the radion originating from the modulus of the theory. The presence of brane cosmological constant renders the branes to be non-flat and gives rise to a potential and a non-canonical kinetic term for the radion field in the four dimensional effective action. The kinetic term exhibits a phantom-like behavior within the domain of evolution of the modulus which leads to a violation of the null-energy condition often observed in a bouncing universe. The interplay of the radion potential and kinetic term enables the evolution of the radion field from a normal to a phantom regime where the universe transits from a contracting era to an expanding epoch through a non-singular bounce. Analysis of the scalar and tensor perturbations over such background evolution reveal that the primordial observables e.g., the amplitude of scalar perturbations As\mathcal{A}_s, tensor to scalar ratio rr and the scalar spectral index nsn_s are in agreement with the current constraints reported by the Planck satellite. The implications are discussed.

Keywords

Cite

@article{arxiv.2011.11886,
  title  = {Bouncing cosmology in a curved braneworld},
  author = {Indrani Banerjee and Tanmoy Paul and Soumitra SenGupta},
  journal= {arXiv preprint arXiv:2011.11886},
  year   = {2021}
}

Comments

JCAP accepted

R2 v1 2026-06-23T20:28:01.292Z