Quintessence with a localized scalar field on the brane

TL;DR

This paper investigates quintessence in brane cosmology with a localized scalar field, revealing effects of bulk black holes and holographic matter on universe acceleration and early universe dynamics.

Contribution

It introduces a model with a localized scalar on the brane and analyzes the impact of bulk black holes, including a $ ho^2$-term and holographic matter, on cosmological evolution.

Findings

$ ho^2$-term induces deceleration in early universe

Holographic matter acts as CFT-radiation in early universe

Model suggests a mechanism to avoid perpetual acceleration

Abstract

We study issues of the quintessence in the brane cosmology. The initial bulk spacetime consists of two 5D topological anti de Sitter black hole joined by the brane (moving domain wall). Here we do not introduce any conventional radiation and matter. Instead we include a localized scalar on the brane as a stress-energy tensor, and thus we find the quintessence which gives an accelerating universe. Importantly, we obtain a $\rho^2$-term as well as a holographic matter term of $\alpha/a^4$ from the masses of the topological black holes. We discuss a possibility that in the early universe, $\rho^2$-term makes a large kinetic term which induces a decelerating universe. This may provide a hint of avoiding from the perpetually accelerating universe of the present-day quintessence. If a holographic matter term exists, it will plays the role of a CFT-radiation in the early universe.