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arXiv 2302.13637gr-qc
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$D\geq4$维Finch-Skea几何中奇异星的最大质量和半径

Maximum mass and radius of strange stars in Finch-Skea geometry in dimensions $D\geq4$

B. Das, K. B. Goswami, A. Saha, P. K. Chattopadhyay

摘要:

在本文中,我们证明了一个由Finch-Skea度规定义的$D\ge4$维时空中含有奇异物质的致密星模型。为了研究内部物质的相关物理性质,我们考虑了$p=\frac{1}{3}(ρ-4B)$在MIT袋模型中提出的状态方程$(henceforth~EOS)$,其中$B$被称为袋常数。在四维和更高的维度中的质量-半径关系是通过关系$ρ_{s}=4B$使用表面密度的值的范围来确定的,对于该关系,大块奇怪物质可能是紧凑物体的可行问题。这里我们选择$B$的范围,使得稳定的奇异物质可以在相对于中子为零的外部压力下存在。我们注意到,当$B$固定在一个给定的允许值时,恒星半径存在一个最大值,在此度量函数被认为是实的。这是该模型中允许的最大半径$(b_{max})$,它取决于奇异星的表面密度。在四维空间中,恒星的紧密度大于0.33。在更高的维度($D>4$)的情况下,我们观察到不同的紧凑性值。因果关系条件满足内部的恒星最大允许半径$(b_{max})$的度量函数是真实的。研究了恒星构型的能量条件、表面红移等参数的有效性,得到了新的结果。并对系统的稳定性进行了研究。

英文摘要:

In this article, we demonstrated a stellar model for compact star in presence of strange matter embedded in $D\ge4$ dimensional space-time defind by Finch-Skea metric. To study the relevant physical properties of the interior matter, we consider the equation of state $(henceforth~EOS)$ as proposed in MIT bag model given by $p=\frac{1}{3}(ρ-4B)$, where $B$ is termed as bag constant. The Mass-Radius relationships in four and higher dimensions are determined using the range of values of surface density through the relation $ρ_{s}=4B$ for which bulk strange matter may be a viable issue for compact objects. Here we choose the range of $B$ such that stable strange matter may exist at zero external pressure relative to neutron. We note that a maximum value of the stellar radius is exist when $B$ is fixed at a given allowed value for which metric functions considered here to be real. This is the maximum allowed radius $(b_{max})$ in this model which depends on surface density of a strange star. In four dimensions the compactness of a star is found to be greater than 0.33. In case of higher dimensions ($D>4$), we observed different values of compactness. Causality conditions are satisfied interior to the star upto maximum allowed radius $(b_{max})$ for which metric function is real. The validity of energy conditions, surface red-shift and other parameters of the stellar configuration are studied and found new results. Stability of the system is also studied.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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