Vacuum Energy Density and Cosmological Constant in dS Brane World

TL;DR

This paper explores the relationship between vacuum energy density, the cosmological constant, and gravity localization in a de Sitter brane world with a dilaton field, providing models consistent with observations.

Contribution

It presents a stable AdS4 brane construction within a dS5 bulk and derives explicit relations between bulk and brane cosmological constants, linking vacuum energy to observable data.

Findings

Stable AdS4 brane can be constructed in dS5 bulk.

Explicit relation between bulk and brane cosmological constants.

Vacuum energy density matches astronomical observations.

Abstract

We discuss the vacuum energy density and the cosmological constant of dS$_5$ brane world with a dilaton field. It is shown that a stable AdS$_4$ brane can be constructed and gravity localization can be realized. An explicit relation between the dS bulk cosmological constant and the brane cosmological constant is obtained. The discrete mass spectrum of the massive scalar field in the AdS$_4$ brane is used to acquire the relationship between the brane cosmological constant and the vacuum energy density. The vacuum energy density in the brane gotten by this method is in agreement with astronomical observations.