# Inflationary RSII Model with a Matter in the Bulk and Exponential   Potential of Tachyon Field

**Authors:** Marko Stojanovi\'c, Neven Bili\'c, Dragoljub D. Dimitrijevi\'c, Goran, S. Djordjevic, Milan Milo\v{s}evi\'c

arXiv: 1904.11329 · 2019-10-18

## TL;DR

This paper investigates an inflationary cosmological model within the RSII framework, incorporating bulk matter and a tachyon field with exponential potential, analyzing how these factors influence inflationary parameters.

## Contribution

It introduces a modified RSII inflationary model with bulk matter affecting tachyon dynamics and numerically evaluates key inflationary observables.

## Key findings

- Bulk matter alters the warp factor and inflation dynamics.
- Numerical estimates of $n_s$ and $r$ for the tachyon model.
- Insights into tachyon-driven inflation in braneworld scenarios.

## Abstract

In this paper we study a tachyon cosmological model based on dynamics of a 3-brane in the second Randall-Sundrum (RSII) model extended to include matter in the bulk. The presence of matter in the bulk changes warp factor which leads to modification of inflationary dynamics. The additional brane behaves effectively as a tachyon. We calculate numerically observation parameters of inflation: the scalar spectral index ($n_s$) and the tensor-to-scalar ratio ($r$) for the exponential potential of tachyon field.

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Source: https://tomesphere.com/paper/1904.11329