DBI-essence

Journal Article · Sun Jun 15 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.77.123508· OSTI ID:21212008

Martin, Jerome; Yamaguchi, Masahide ^[1]

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1. Institut d'Astrophysique de Paris, UMR 7095-CNRS, Universite Pierre et Marie Curie, 98bis boulevard Arago, 75014 Paris (France)

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 -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.

• OSTI ID: 21212008
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 12 Vol. 77; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATTRACTORS
BORN-INFELD THEORY
COMPARATIVE EVALUATIONS
EQUATIONS OF STATE
EXPECTATION VALUE
MASS
MATHEMATICAL SOLUTIONS
NONLUMINOUS MATTER
POTENTIALS
RED SHIFT
SCALAR FIELDS
SCALING