Enhanced inflation in the Dirac-Born-Infeld framework

Journal Article · Tue Mar 15 00:00:00 EDT 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.063505· OSTI ID:21537498

Chimento, Luis P; Richarte, Martin G ^[1]; Lazkoz, Ruth ^[2]

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1. Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina)
2. Fisika Teorikoa, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 Posta Kutxatila, 48080 Bilbao (Spain)

We consider the Einstein equations within the Dirac-Born-Infield (DBI) scenario for a spatially flat Friedmann-Robertson-Walker (FRW) spacetime without a cosmological constant. We derive the inflationary scenario by applying the symmetry transformations which preserve the form of the Friedmann and conservation equations. These form invariance transformations generate a symmetry group parametrized by the Lorentz factor {gamma}. We explicitly obtain an inflationary scenario by the cooperative effect of adding energy density into the Friedmann equation. For the case of a constant Lorentz factor, and under the slow roll assumption, we find the transformation rules for the scalar and tensor power spectra of perturbations as well as their ratio under the action of the form invariance symmetry group. Within this case and due to its relevance for the inflationary paradigm, we find the general solution of the dynamical equations for a DBI field driven by an exponential potential and show a broad set of inflationary solutions. The general solution can be split into three subsets and all these behave asymptotically as a power-law solution at early and at late times.

• OSTI ID: 21537498
• Journal Information: Physical Review. D, Particles Fields, Vol. 83, Issue 6; Other Information: DOI: 10.1103/PhysRevD.83.063505; (c) 2011 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BORN-INFELD THEORY
COSMOLOGICAL CONSTANT
DIRAC COSMOLOGY
DISTURBANCES
EINSTEIN FIELD EQUATIONS
ENERGY DENSITY
INFLATIONARY UNIVERSE
MATHEMATICAL SOLUTIONS
PERTURBATION THEORY
SPACE-TIME
SPECTRA
SYMMETRY
SYMMETRY GROUPS
TRANSFORMATIONS
COSMOLOGICAL MODELS
COSMOLOGY
EQUATIONS
FIELD EQUATIONS
MATHEMATICAL MODELS