标题： 可行的f(R)引力理论的宇宙学动力学 显示英文标题

标题： Cosmological dynamics of viable f(R) theories of gravity

摘要： 对广义相对论的Hu-Sawicki修正的动力学进行了完整的分析。 特别是，给出了当模型参数取为n=1，c1=1时的完整相空间，同时识别出几个稳定的德西特平衡点以及一个不稳定的“物质类似”点。 我们发现，如果选择宇宙学参数今天取Lambda CDM的值，这会导致一个宇宙，在非常低的红移之前，由等于t1/3的状态方程参数主导，从而导致与Lambda CDM非常不同的膨胀历史。 我们证明，通过在高红移处选择Lambda CDM初始条件并将其方程积分到今天，可以解决这个问题。 显示英文摘要

摘要： A complete analysis of the dynamics of the Hu-Sawicki modification to General Relativity is presented. In particular, the full phase-space is given for the case in which the model parameters are taken to be n=1, c1=1, and several stable de Sitter equilibrium points together with an unstable "matter-like" point are identified. We find that if the cosmological parameters are chosen to take on their Lambda CDM values today, this results in a universe which, until very low redshifts, is dominated by an equation of state parameter equal t1/3, leading to an expansion history very different from Lambda CDM. We demonstrate that this problem can be resolved by choosing Lambda CDM initial conditions at high redshifts and integrating the equations to the present day.