Soft coincidence in late acceleration

Journal Article · Wed Jun 15 00:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.71.123529· OSTI ID:20709544

Campo, Sergio del ^[1]; Herrera, Ramon ^[2]; Pavon, Diego ^[3]

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1. Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Casilla 4059, Valparaiso (Chile)
2. Departamento de Ciencias Fisicas, Universidad Andres Bello, Avenida Republica 273, Santiago (Chile)
3. Departamento de Fisica, Facultad de Ciencias, Universidad Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)

We study the coincidence problem of late cosmic acceleration by assuming that the present ratio between dark matter and dark energy is a slowly varying function of the scale factor. As the dark energy component we consider two different candidates, first a quintessence scalar field, and then a tachyon field. In either case analytical solutions for the scale factor, the field, and the potential are derived. Both models show a good fit to the recent magnitude-redshift supernovae data. However, the likelihood contours disfavor the tachyon field model as it seems to prefer a excessively high value for the matter component.

• OSTI ID: 20709544
• Journal Information: Physical Review. D, Particles Fields, Vol. 71, Issue 12; Other Information: DOI: 10.1103/PhysRevD.71.123529; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCELERATION
ANALYTICAL SOLUTION
COSMOLOGY
NONLUMINOUS MATTER
POTENTIALS
SCALAR FIELDS
SUPERNOVAE