Gravitational collapse of massless scalar field in $f(R)$ gravity
Gravitational collapse of massless scalar field in $f(R)$ gravity
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DOI：
10.1103/physrevd.94.104013
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发表时间：
2016-08
影响因子：
5
通讯作者：
Cheng-Yong Zhang;Zi-Yu Tang;Bin Wang
中科院分区：
文献类型：
--
作者：
Cheng-Yong Zhang;Zi-Yu Tang;Bin Wang
研究了无质量标量物质场在Starobinsky{R}^{2}$引力下渐近平坦时空中的球对称引力坍缩.在爱因斯坦的$f(R)$引力框架中，由于保角变换产生了一个额外的标量场。我们发现，除了通常在引力坍缩过程中引力能和动能之间的竞争之外，保角变换带来的新的标量场在动力系统中增加了一种新的竞争力量。通过调节新标量场和物质场初始微扰的幅度，可以控制动力学竞争。为了理解这些现象背后的物理原因，我们分析了引力势行为，并计算了中心的Ricci标量随初始微扰幅度的变化。我们发现了丰富的物理学关于黑洞的形成通过引力崩塌在$f(R)$重力。
We study the spherically symmetric gravitational collapse of massless scalar matter field in asymptotic flat spacetime in the Starobinsky ${R}^{2}$ gravity, one specific model in the $f(R)$ gravity. In the Einstein frame of $f(R)$ gravity, an additional scalar field arises due to the conformal transformation. We find that in addition to the usual competition between gravitational energy and kinetic energy in the process of gravitational collapse, the new scalar field brought by the conformal transformation adds one more competing force in the dynamical system. The dynamical competition can be controlled by tuning the amplitudes of the initial perturbations of the new scalar field and the matter field. To understand the physical reasons behind these phenomena, we analyze the gravitational potential behavior and calculate the Ricci scalar at center with the change of initial amplitudes of perturbations. We find rich physics on the formation of black holes through gravitational collapse in $f(R)$ gravity.