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Soft coincidence in late acceleration

Sergio del campo·Ramon Herrera·Diego Pavon
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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 dark energy component we consider two different candidates, first a quintessence scalar field, and then a tachyon field. In either cases 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.

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Sergio del campo, Ramon Herrera, Diego Pavon. 2005-06-21. Soft coincidence in late acceleration. https://doi.org/10.1103/physrevd.71.123529

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