Abstract
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. © 2005 The American Physical Society.
Original language | English |
---|---|
Article number | 123529 |
Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |
Volume | 71 |
DOIs | |
Publication status | Published - 15 Jun 2005 |