Soft coincidence in late acceleration
Soft coincidence in late acceleration
复制标题
DOI：
10.1103/physrevd.71.123529
复制
发表时间：
2005-06
影响因子：
5
通讯作者：
S. Campo;R. Herrera;D. Pavón
中科院分区：
文献类型：
--
作者：
S. Campo;R. Herrera;D. Pavón
通过假定暗物质和暗能量的当前比是标度因子的缓变函数，研究了宇宙晚期加速的符合问题。作为暗能量分量，我们考虑了两个不同的候选者，首先是经典标量场，然后是快子场。在这两种情况下，都得到了标度因子、场和势的解析解。这两个模型都显示出与最近的星等红移超新星数据很好的吻合。然而，可能性等值线不支持快子场模型，因为它似乎倾向于物质分量的过高值。
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.