2008/01/22 by Jerome Martin, Jérôme Martin, Masahide Yamaguchi · 1 citation
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Cosmology and Gravitation Theories #Microtubule and mitosis dynamics #Mitochondrial Function and Pathology #astro-ph #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.77.123508
published as Phys.Rev.D77:123508,2008 · 9 pages, 4 figures
arxiv created 2008/01/22 · openalex publication_date 2008/06/09 · arxiv updated 2009/12/01 · openalex created_date 2020/07/02 · openalex updated_date 2026/07/28
Models where the dark energy is a scalar field with a nonstandard Dirac-Born-Infeld (DBI) kinetic term are investigated. Scaling solutions are studied and proven to be attractors. The corresponding shape of the brane tension and of the potential is also determined and found to be, as in the standard case, either exponentials or power law of the DBI field. In these scenarios, in contrast to the standard situation, the vacuum expectation value of the field at small redshifts can be small in comparison to the Planck mass which could be an advantage from the model building point of view. This situation arises when the present-day value of the Lorentz factor is large, this property being per se interesting. Serious shortcomings are also present such as the fact that, for simple potentials, the equation of state appears to be too far from the observational favored value \ensuremath-1. Another problem is that, although simple stringy-inspired models precisely lead to the power-law shape that has been shown to possess a tracking behavior, the power index turns out to have the wrong sign. Possible solutions to these issues are discussed.