Inflation in DBI models with constant {gamma}

Journal Article · Tue Apr 15 04:00:00 EDT 2008 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2008/04/002· OSTI ID:22137827

Spalinski, Michal ^[1]

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1. Soltan Institute for Nuclear Studies, ulica Hoza 69, PL-00-681 Warszawa (Poland)

Dirac-Born-Infeld scalar field theories which appear in the context of inflation in string theory in general have a field-dependent speed of sound. It is, however, possible to write down DBI models which possess exact solutions characterized by a constant speed of sound different from unity. This requires that the potential and the effective D-brane tension appearing in a DBI action have to be related in a specific way. This paper describes such models in general and presents some examples with a constant speed of sound c{sub s}<1 for which the spectrum of scalar perturbations can be found analytically without resorting to the slow-roll approximation.

• OSTI ID: 22137827
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 04 Vol. 2008; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
79 ASTRONOMY AND ASTROPHYSICS
BORN-INFELD THEORY
D-BRANES
DISTURBANCES
EXACT SOLUTIONS
INFLATIONARY UNIVERSE
SCALAR FIELDS
SOUND WAVES
SPECTRA
STRING THEORY