Accelerating universes driven by bulk particles
Abstract
We consider our universe as a 3d domain wall embedded in a 5d dimensional Minkowski spacetime. We address the problem of inflation and late time acceleration driven by bulk particles colliding with the 3d domain wall. The expansion of our universe is mainly related to these bulk particles. Since our universe tends to be permeated by a large number of isolated structures, as temperature diminishes with the expansion, we model our universe with a 3d domain wall with increasing internal structures. These structures could be unstable 2d domain walls evolving to fermiballs which are candidates to cold dark matter. The momentum transfer of bulk particles colliding with the 3d domain wall is related to the reflection coefficient. We show a nontrivial dependence of the reflection coefficient with the number of internal dark matter structures inside the 3d domain wall. As the population of such structures increases the velocity of the domain wall expansion also increases. The expansion is exponential at early times and polynomial at late times. We connect this picture with string/Mtheory by considering BPS 3d domain walls with structures which can appear through the bosonic sector of a fivedimensional supergravity theory.
 Publication:

Physical Review D
 Pub Date:
 April 2005
 DOI:
 10.1103/PhysRevD.71.083516
 arXiv:
 arXiv:hepth/0502057
 Bibcode:
 2005PhRvD..71h3516B
 Keywords:

 98.80.Cq;
 11.10.Lm;
 95.35.+d;
 Particletheory and fieldtheory models of the early Universe;
 Nonlinear or nonlocal theories and models;
 Dark matter;
 High Energy Physics  Theory;
 Astrophysics;
 Condensed Matter  Soft Condensed Matter
 EPrint:
 To appear in Phys. Rev. D, 16 pages, 3 eps figures, minor changes and references added