Tachyon inflation in the holographic braneworld

Abstract

A model of tachyon inflation is proposed in the framework of holographic cosmology. The model is based on a holographic braneworld scenario with a D3-brane located at the holographic boundary of an asymptotic ADS${}_5$ bulk. The tachyon field that drives inflation is represented by a DBI action on the brane. We solve the evolution equations analytically in the slow-roll regime and solve the exact equations numerically. We calculate the inflation parameters and compare the results with Planck 2018 data.

27 pages 6 figures, substantially revised version accepted for publication in JCAP. A comment on primordial non-Gaussianity added, an appendix on cosmological perturbations added, a minor mistake in the equation for spectral density corrected resulting in slight modifications of the plots, 7 references added, typos corrected