Age constraints and fine tuning in variable-mass particle models
Age constraints and fine tuning in variable-mass particle models
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变质量粒子模型中的年龄限制和微调
DOI：
10.1103/physrevd.69.063517
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发表时间：
2003
影响因子：
5
通讯作者：
R. Rosenfeld
中科院分区：
文献类型：
--
作者：
Urbano França;R. Rosenfeld
VAMP（变质量粒子）方案，其中冷暗物质粒子的质量是导致宇宙加速的标量场的函数，已经被提出作为宇宙巧合问题的解决方案，因为在吸引子制度中，暗能量和暗物质以相同的方式标度。我们发现，只有一个狭窄的区域参数空间导致模型与可行的值的哈勃常数和暗能量密度今天。在允许的范围内，暗能量密度开始在当前时期占主导地位，因此这些模型不能解决符合问题。我们表明，在这种情况下的宇宙年龄是相当高的年龄非耦合暗能量模型，并得出结论，更精确的独立测量宇宙的年龄将是有用的，在耦合和非耦合暗能量模型之间的区别。
VAMP (variable-mass particles) scenarios, in which the mass of the cold dark matter particles is a function of the scalar field responsible for the present acceleration of the Universe, have been proposed as a solution to the cosmic coincidence problem, since in the attractor regime both dark energy and dark matter scale in the same way. We find that only a narrow region in parameter space leads to models with viable values for the Hubble constant and dark energy density today. In the allowed region, the dark energy density starts to dominate around the present epoch and consequently such models cannot solve the coincidence problem. We show that the age of the Universe in this scenario is considerably higher than the age for noncoupled dark energy models, and conclude that more precise independent measurements of the age of the Universe would be useful in distinguishing between coupled and noncoupled dark energy models.