arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1906.04570gr-qc
收藏

因果热力学中耗散暗物质的检验

Testing dissipative dark matter in causal thermodynamics

Norman Cruz, Esteban González, Guillermo Palma

摘要:

在本文中,我们研究了宇宙模型的一致性表示一个充满了一个单组分耗散暗物质流体的宇宙,在因果的Israel-Stewart理论的框架下,其中所产生的一般表达式从微扰分析的弛豫时间$τ$。该模型由最近在[N. Cruz,E. González和G. Palma,Gen. Rel.重力\textbf{52},62(2020),它取决于几个模型参数以及积分常数,允许使用Ia型超新星和观测哈勃数据来执行收敛的观测测试。为解的参数找到的约束区域允许在粘性压力的支配时代之后的后期存在宇宙的加速膨胀,这在不需要包括宇宙学常数的情况下成立。然而,拟合的参数值导致的缺点,作为一个非常大的非绝热贡献的声速,和一些不一致,不完全决定性的,与描述的耗散暗物质作为一种流体,这仍然是这些类型的模型的共同特征。

英文摘要:

In this paper we study the consistency of a cosmological model representing a universe filled with a one-component dissipative dark matter fluid, in the framework of the causal Israel-Stewart theory, where a general expression arising from perturbation analysis for the relaxation time $τ$ is used. This model is described by an exact analytic solution recently found in [N. Cruz, E. González and G. Palma, Gen. Rel. Grav. \textbf{52}, 62 (2020), which depends on several model parameters as well as integration constants, allowing the use of Type Ia Supernovae and Observational Hubble data to perform an astringent observational test. The constraint regions found for the parameters of the solution allow the existence of an accelerated expansion of the universe at late times, after the domination era of the viscous pressure, which holds without the need of including a cosmological constant. Nevertheless, the fitted parameter values lead to drawbacks as a very large non-adiabatic contribution to the speed of sound, and some inconsistencies, not totally conclusive, with the description of the dissipative dark matter as a fluid, which is nevertheless a common feature of these kind of models.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑