We consider a D3-brane as boundary of a five dimensional charged anti de Sitter black hole. We show that the charge of the black hole induces a regular cosmological evolution for the scale factor of the brane, with a smooth transition between a contracting and an eventual expanding phase. Simple analytical solutions can be obtained in the case of a vanishing effective cosmological constant on the brane. A nonvanishing cosmological constant, or the inclusion of radiation on the brane, does not spoil the regularity of these solutions at small radii, and observational constraints such as the ones from primordial nucleosynthesis can be easily met. Fluctuations of brane fields remain in the linear regime provided the minimal size of the scale factor is sufficiently large. We conclude with an analysis of the Cardy-Verlinde formula in this set up.Comment: 13 pages, final versio

We obtain a large class of cosmological solutions in the toroidally-compactified low energy limits of string theories in D dimensions. We consider solutions where a p-dimensional subset of the spatial coordinates, parameterising a flat space, a sphere, or an hyperboloid, describes the spatial sections of the physically-observed universe. The equations of motion reduce to Liouville or SL(N + 1, R) Toda equations, which are exactly solvable. We study some of the cases in detail, and find that under suitable conditions they can describe four-dimensional expanding universes. We discuss also how the solutions in D dimensions behave upon oxidation back to the D = 10 string theory or D = 11 M-theory.

We calculate the correction to the Bekenstein-Hawking entropy formula for five dimensional AdS-Schwarzschild black holes due to thermodynamic fluctuations. The result is then compared with the boundary gauge theory entropy corrections via AdS/CFT correspondence. We then further generalise our analysis for the rotating black hole in five dimensional AdS space. 1

This is a continuation of our earlier work where we constructed a phenomenologically motivated effective action of the boundary gauge theory at finite temperature and finite gauge coupling on S 3 × S 1 . In this paper, we argue that this effective action qualitatively reproduces the gauge theory representing various bulk phases of R-charged black hole with GaussBonnet correction. We analyze the system both in canonical and grand canonical ensemble.