迄今，中子星的狀態方程式仍然尚未有定論。由於在廣義相對論裡面探討緻密星體時，狀態方程式一般都從粒子物理以及統計力學的觀點算出而不與廣義相對論直接相關，因此廣義相對論對可行的狀態方程式限制不大。

在這文章中，我們希望能從考慮R平方（Starobinsky）重力模型 f(R) = R + αR^2 及其所得出之修正的Tolman-Oppenheimer-Volkoff(TOV)方程式進而給出可行的狀態方程式多一些限制，而非以粒子和統計物理為出發點考慮此問題。

Until now, the equation of state of the neutron star is still an open question. Since the equation of state is usually derived from the starting point of particle physics and statistical mechanics when studying the compact star under the scheme of General Relativity (GR), GR doesn’t impinge on the physical equation of state directly.
In this work, we consider the R-squared (Starobinsky) model of gravity f(R) = R + αR^2 and obtain the modified TOV equation in an attempt to give more constraints on the equation of state rather than the standard GR scheme.

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