标题： 从观测约束的粘性宇宙学中重构$f(R)$引力 显示英文标题

标题： Reconstructing $f(R)$ gravity from viscous cosmology constrained by observations

摘要： 在本文中，我们使用受多种不同天体物理观测约束的粘滞$\omega$冷暗物质情景（V-$\omega$CDM），重构了$f(R)$理论，这些观测包括Ia型超新星（SNe Ia）、观测哈勃参数数据（OHD）、威尔金森微波各向异性探测器9年数据（WMAP-9）、普朗克观测以及最新事件GW150914（GW）的单个数据点。我们发现，SNe Ia+OHD+Planck+GW数据集的联合约束对V-$\omega$CDM情景的参数给出了更严格的限制。随后，我们发现这些重构的$f(R)$理论在过去存在显著的简并性，并且它们在当前时代开始表现出不同的演化行为，以及在遥远的未来也有很大差异。 此外，我们还比较了重构的$f(R)$理论与 V-$\omega$CDM 情景以及使用 SNe Ia+OHD+Planck+GW 数据集在$f(R)-R$平面上约束的$\omega$CDM 情景，发现这两种情景存在极高的退化性，这意味着在宇宙整个演化过程中，大尺度粘滞效应在 V-$\omega$CDM 模型中起着可以忽略的作用。 此外，还可以发现，使用这两种模型重构的$f(R)$理论仅稍微偏离了标准爱因斯坦引力。 显示英文摘要

摘要： In this paper, we reconstruct the $f(R)$ theory using the viscous $\omega$CDM scenario (V-$\omega$CDM) constrained by several differently astrophysical observations, including Type Ia supernovae (SNe Ia), observational Hubble parameter data (OHD), Wilkinson Microwave Anisotropy Probe 9-year data (WMAP-9), Planck observations and the single data point from the newest event GW150914 (GW). We find that the joint constraints from SNe Ia+OHD+Planck+GW data-sets give out a tighter restriction for the parameters of the V-$\omega$CDM scenario than other constraints. Subsequently, we find that there exists a substantially high degeneracy among these reconstructed $f(R)$ theories in the past, and that they start exhibiting differently evolutional behaviors around the present epoch as well as much different in the distant future. Furthermore, we make a comparison between the reconstructed $f(R)$ theory with the V-$\omega$CDM scenario and that with the $\omega$CDM scenario constrained by using the SNe Ia+OHD+Planck+GW data-sets in the $f(R)-R$ plane, and find that the two scenarios share an extremely high degeneracy, which implies that the effect of bulk viscosity plays a negligible role in the V-$\omega$CDM model during the whole evolutionary processes of the universe. In addition, one can also find that the reconstructed $f(R)$ theories using the two models just deviate from the standard Einstein gravity a little.