论文标题
在$ f(r,t)中探索紧凑型星的物理特性 - $重力:一种嵌入方法
Exploring physical properties of compact stars in $f(R,T)-$gravity: An embedding approach
论文作者
论文摘要
恰好在$ f(r,t)$重力中求解场方程是一项艰巨的任务之一。为此,许多作者采用了不同的方法,例如假设度量函数,状态方程(EOS)和度量函数等方程等。但是,这种方法可能并不总是导致行为良好的解决方案,从而在完整计算后可能会发生拒绝解决方案。的确,关于嵌入一级方法的最新作品表明,到达表现良好的解决方案的机会很高,从而激发了我们使用它。在第一类方法中,我们必须获得ANSATZ的一个度量电位之一,另一个可以从Karmarkar条件中获得。在本文中,我们提出了新的第一类解决方案,该解决方案在所有物理观点中都表现得很好。我们已经通过调整$ f(r,t) - $耦合参数$χ$来分析解决方案的性质,并发现该解决方案以$χ= -1 $大于$χ= 1 $的变化EOS结果。这是因为对于$χ$的较小值,声音的速度更高,$ m-m-r $曲线中的$ m_ {max} $,eos参数$ω$更大。该解决方案满足了径向扰动(静态稳定性标准)和平衡(修改TOV-方程式)下的因果关系,能量条件,稳定和静态的。该解决方案中产生的$ M-R $图与几个紧凑型恒星的观察值非常拟合,例如PSR J1614-2230,Vela X-1,CEN X-1,CEN X-1和SAX J1808.4-3658。因此,对于$χ$的不同值,我们已经预测了相应的半径及其各自的惯性时刻。
Solving field equations exactly in $f(R,T)$ gravity is one of the difficult task. To do so, many authors have adopted different methods such as assuming both the metric functions, an equation of state (EoS) and a metric function etc. However, such methods may not always lead to well-behaved solutions and thereby rejection of the solutions may happen after complete calculations. Indeed, very recent works on embedding class one methods suggested that the chances of arriving at the well behaved-solution is very high thereby inspired us to used it. In class one approach, we have to ansatz one of the metric potentials and the other can be obtain from the Karmarkar condition. In this paper, we are proposing new class one solution which is well-behaved in all physical points of view. We have analyzed the nature of the solution by tuning the $f(R,T)-$coupling parameter $χ$ and found that the solution results into stiffer EoS for $χ=-1$ than $χ=1$. This is because for lesser values of $χ$, velocity of sound is more, higher $M_{max}$ in $M-R$ curve and the EoS parameter $ω$ is larger. The solution satisfy the causality condition, energy conditions, stable and static under radial perturbations (static stability criterion) and in equilibrium (modified TOV-equation). The resulting $M-R$ diagram from this solution is well fitted with observed values of few compact stars such as PSR J1614-2230, Vela X-1, Cen X-3 and SAX J1808.4-3658. Therefore, for different values of $χ$, we have predicted the corresponding radii and their respective moment of inertia from the $M-I$ curve.