Global Black Branes (Extended Global Defects Surrounded by Horizons), Brane Worlds and the Cosmological Constant

Abstract

We study global defects coupled to higher-dimensional gravity with a negative cosmological constant. This paper is mainly devoted to studying global black brane solutions which are extended global defects surrounded by horizons. We find series solutions in a few separated regions and confirm numerically that they can be mutually connected. When the world volume of the brane is Ricci-flat, the brane is surrounded by a degenerated horizon, while it is surrounded by two horizons when the world volume has a positive constant curvature. Each solution corresponds to an extremal and a non-extremal state, respectively. Their causal structures resemble those of the Reissner-Nordstr\"{o}m black holes in anti-de Sitter spacetime. However, the non-extremal black brane is not a static object, but an inflating brane. In addition, we briefly discuss a brane world model in the context of the global black branes. We comment on a few thermodynamic properties of the global black branes, and discuss a decrease of the cosmological constant on the brane world through the thermodynamic instability of the non-extremal global black brane.