论文标题
$ f（r）$ gravity的可遍历的虫洞具有消失的声速
Traversable wormholes with vanishing sound speed in $f(R)$ gravity
论文作者
论文摘要
我们在$ f（r）$重力的框架中得出了可遍历的虫洞溶液，没有异国情调的物质，并且在进入喉咙的几何流体上具有稳定的条件。为此，我们提出了PowerLaw $ F（R）$型号和形状函数$ B（R）/R $的两种可能的方法。第一种方法利用了反功率定律功能，即$ b（r）/r \ sim r^{ - 1-β} $。第二个采用Padé近似值，用于以模型无关的方式表征形状函数。如果声速以$ r = r_0 $消失，我们会挑出$ p（0,1）$近似值，其中喉咙内的流体扰动可以忽略不计。前者保证了几何流体在虫洞中的总体稳定性。最后，对于上述讨论的情况，我们在模型的参数上获得了适当的界限。总之，我们发现与一般相对论的小偏差给出了稳定的解决方案。
We derive exact traversable wormhole solutions in the framework of $f(R)$ gravity with no exotic matter and with stable conditions over the geometric fluid entering the throat. For this purpose, we propose power-law $f(R)$ models and two possible approaches for the shape function $b(r)/r$. The first approach makes use of an inverse power law function, namely $b(r)/r\sim r^{-1-β}$. The second one adopts Padé approximants, used to characterize the shape function in a model-independent way. We single out the $P(0,1)$ approximant where the fluid perturbations are negligible within the throat, if the sound speed vanishes at $r=r_0$. The former guarantees an overall stability of the geometrical fluid into the wormhole. Finally we get suitable bounds over the parameters of the model for the above discussed cases. In conclusion, we find that small deviations from General Relativity give stable solutions.
