Note on the equivalence of a barotropic perfect fluid with a k-essence scalar field

Journal Article · Sat May 15 04:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.107301· OSTI ID:21409797

Arroja, Frederico; Sasaki, Misao ^[1]

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1. Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

In this brief report, we obtain the necessary and sufficient condition for a class of noncanonical single scalar field models to be exactly equivalent to barotropic perfect fluids, under the assumption of an irrotational fluid flow. An immediate consequence of this result is that the nonadiabatic pressure perturbation in this class of scalar field systems vanishes exactly at all orders in perturbation theory and on all scales. The Lagrangian for this general class of scalar field models depends on both the kinetic term and the value of the field. However, after a field redefinition, it can be effectively cast in the form of a purely kinetic k-essence model.

• OSTI ID: 21409797
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 10 Vol. 81; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
DISTURBANCES
FLUID FLOW
FUNCTIONS
IDEAL FLOW
INCOMPRESSIBLE FLOW
LAGRANGIAN FUNCTION
PERTURBATION THEORY
SCALAR FIELDS
STEADY FLOW