arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1701.00780gr-qcastro-ph.CO
收藏

一个新的相互作用双流体模型及其结果

A new interacting two fluid model and its consequences

German S. Sharov, Subhra Bhattacharya, Supriya Pan, Rafael C. Nunes, Subenoy Chakraborty

摘要:

在具有零空间曲率的均匀各向同性时空背景下,考虑了无压暗物质(DM)和暗能量(DE)两种正压流体之间的相互作用,其中DE中的状态方程(EoS)是常数或时间依赖的.特别是,对于常数EoS DE,我们表明,这两种流体的演化方程可以解析求解。对于所有这些情况下,模型参数已被约束使用当前的天文观测Ia型超新星,哈勃参数测量,和重子声学振荡距离测量。我们的分析表明,对于DE中的恒定和可变EoS,暗扇区中的非常小但非零的相互作用是有利的,而DE中的EoS可以预测轻微的幻影性质,即DE中的EoS可以穿过幻影分界线“$-1$”。另一方面,虽然具有可变EoS的模型更好地描述了观测值,但赤池信息准则支持具有最少数量的参数的模型。然而,我们发现所有的模型都非常接近于$Λ$ CDM宇宙学。

英文摘要:

In the background of a homogeneous and isotropic spacetime with zero spatial curvature, we consider interacting scenarios between two barotropic fluids, one is the pressureless dark matter (DM) and the other one is dark energy (DE), in which the equation of state (EoS) in DE is either constant or time dependent. In particular, for constant EoS in DE, we show that the evolution equations for both fluids can be analytically solved. For all these scenarios, the model parameters have been constrained using the current astronomical observations from Type Ia Supernovae, Hubble parameter measurements, and baryon acoustic oscillations distance measurements. Our analysis shows that both for constant and variable EoS in DE, a very small but nonzero interaction in the dark sector is favored while the EoS in DE can predict a slight phantom nature, i.e. the EoS in DE can cross the phantom divide line `$-1$'. On the other hand, although the models with variable EoS describe the observations better, but the Akaike Information Criterion supports models with minimal number of parameters. However, it is found that all the models are very close to the $Λ$CDM cosmology.

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。

↑