IPM
30
YEARS OLD

## “School of Astronomy”

Paper   IPM / Astronomy / 15843
School of Astronomy
Title: Charged Vector Inflation
Author(s):
 1 . Hassan . Firouzjahi 2 . Mohammad Ali . Gorji 3 . Seyed Ali . Hosseini Mansoori 4 . Asieh . Karami 5 . Tahereh . Rostami
Status: Published
Journal: Phys. Rev. D
Vol.: 100
Year: 2019
Supported by:           ipm IPM
Abstract:
We present a model of inflation in which the inflaton field is charged under a triplet of U ( 1 ) gauge fields. The model enjoys an internal O ( 3 ) symmetry supporting the isotropic FRW solution. With an appropriate coupling between the gauge fields and the inflaton field, the system reaches an attractor regime in which the gauge fields furnish a small constant fraction of the total energy density. We decompose the scalar perturbations into the adiabatic and entropy modes and calculate the contributions of the gauge fields into the curvature perturbations power spectrum. We also calculate the entropy power spectrum and the adiabatic-entropy cross-correlation. In addition to the metric tensor perturbations, there are tensor perturbations associated with the gauge field perturbations that are coupled to metric tensor perturbations. We show that the correction in the primordial gravitational tensor power spectrum induced from the matter tensor perturbation is a sensitive function of the gauge coupling.