论文标题
在F（R）重力的Hu-Sawicki模型中模仿暗物质的标量
Scalarons mimicking Dark Matter in the Hu-Sawicki model of f(R) gravity
论文作者
论文摘要
在本文中，我们通过$ \ mathit {f（r）} $重力进行了一项研究，该研究通过时空度量$ g_ {μν} $从约旦框架到爱因斯坦框架的weyl转换。标量场是由于爱因斯坦磁场方程的一般相对性的几何部分的修饰而获得的。对于$ \ mathit {f（r）} $重力的Hu-Sawicki模型，我们找到了标量场的有效潜力并计算其质量。我们的研究表明，从该模型获得的标量场（也称为标量）具有变色位特性，即\ \ scalaron在低密度区域中变得轻度，而在物质的高密度区域则变得很重。然后发现标量可以被视为暗物质（DM）候选者，因为发现标量质量非常接近超轻轴的质量，即主要的DM候选者。因此，$ \ mathit {f（r）} $重力的Hu-Sawicki模型中的标量表现为DM。此外，还进行了对标量质量与红移的演变的研究，该研究描绘了宇宙膨胀随着宇宙不同阶段的不同速率而变成光线。
In this paper, we conduct a study on the scalar field obtained from $\mathit{f(R)}$ gravity via Weyl transformation of the spacetime metric $g_{μν}$ from the Jordan frame to the Einstein frame. The scalar field is obtained as a result of the modification in the geometrical part of Einstein's field equation of General Relativity. For the Hu-Sawicki model of $\mathit{f(R)}$ gravity, we find the effective potential of the scalar field and calculate its mass. Our study shows that the scalar field (also named as scalaron) obtained from this model has the chameleonic property, i.e.\ the scalaron becomes light in the low-density region while it becomes heavy in the high-density region of matter. Then it is found that the scalaron can be regarded as a dark matter (DM) candidate since the scalaron mass is found to be quite close to the mass of ultralight axions, a prime DM candidate. Thus the scalaron in the Hu-Sawicki model of $\mathit{f(R)}$ gravity behaves as DM. Further, a study on the evolution of the scalaron mass with the redshift is also carried out, which depicts that scalaron becomes light with expansion of the Universe and with different rates at different stages of the Universe.
