论文标题
与局部暗能量外壳紧凑的物体
Compact Object with a Local Dark Energy Shell
论文作者
论文摘要
我们基于两个密度曲线的宇宙常数$λ$在一般相对论理论中研究了一些模型，其中一个归因于斯图尔特，另一个归因于durgapal和bannerji，在文献中提出了模型“中子星”。对于他们来说，由于选定的度量，获得了具有宇宙常数的非局部状态方程。在另一个方向上，我们获得了用于无径向压力的构型的解决方案。第一个模型（基于Stewart的密度剖面）原来是最有趣的，因为令人惊讶的是，它在恒星内部，最外层的层中承认了一定范围的Mass-Radius比率$γ$。这种暗能与宇宙常数无关，因为它是流体的切向压力的结果。仍然在这种情况下，对于$γ$的其他值，满足所有能源条件。该模型的另一个优点，以及基于Durgapal和Bannnerji的密度曲线的另一个优点是存在$γ$的间隔，与$λ<0 $，$λ= 0 $和$λ> 0 $兼容的$γ$的间隔，这也允许我们分析$λ$对能量条件的影响。这里研究的其他配置，$ p_r = 0 $，仅允许$λ<0 $的解决方案，以确保对象的正质量并满足特定范围内的所有能量条件。
We investigate some models of compact objects in the general relativity theory with cosmological constant $Λ$, based on two density profiles, one of them attributed to Stewart and the other one to Durgapal and Bannerji, proposed in the literature to model "neutron stars". For them, a nonlocal equation of state with cosmological constant is obtained as a consequence of the chosen metric. In another direction, we obtain a solution for configurations with null radial pressure. The first model (based on the Stewart's density profile) turned out to be the most interesting, since surprisingly it admits the presence of dark energy in the interior of the star, in the outermost layers, for a certain range of mass-radius ratio $γ$. This dark energy is independent of the cosmological constant, since it is a consequence of the tangential pressure of the fluid be sufficiently negative. Still in this case, for other values of $γ$, all the energy conditions are satisfied. Another advantage of this model, as well as that based on the density profile of Durgapal and Bannnerji is the existence of intervals of $γ$ compatible with physically acceptable models for $Λ< 0$, $Λ= 0$ and $Λ> 0$, which also allowed us to analyze the influence of $Λ$ on the behavior of the fluid with respect to the energy conditions. The other configuration studied here, $P_r=0$, only allow solutions for $Λ<0$, in order to ensure a positive mass for the object and to satisfy all the energy conditions in a specific range of $γ$.
