Anti-screening of the Galileon force around a disk center hole
Anti-screening of the Galileon force around a disk center hole
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DOI：
10.1142/s0217732319500135
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发表时间：
2018-02
影响因子：
1.4
通讯作者：
H. Ogawa;T. Hiramatsu;Tsutomu Kobayashi
中科院分区：
文献类型：
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作者：
H. Ogawa;T. Hiramatsu;Tsutomu Kobayashi
Vainshtein机制被认为是在修正重力条件下筛选物质源周围第五种力的有效方法。这主要是在高度对称的物质组态中得到验证的。为了研究Vainshtein机制在较不对称的情况下如何工作，我们数值求解了立方伽利略理论中中心有孔的圆盘周围的标量场方程。令人惊讶的是，我们发现伽利略力在黑洞附近被增强了，而不是被抑制了。对于具有较小孔的较薄、较小质量的盘，这种抗屏蔽效果较大。在这个阶段，我们的设置只是学术上的兴趣，其天体物理后果尚不清楚，但这一结果表明，围绕较不对称的物质配置的Vainshtein筛选机制相当不平凡。
The Vainshtein mechanism is known as an efficient way of screening the fifth force around a matter source in modified gravity. This has been verified mainly in highly symmetric matter configurations. To study how the Vainshtein mechanism works in a less symmetric setup, we numerically solve the scalar field equation around a disk with a hole at its center in the cubic Galileon theory. We find, surprisingly, that the Galileon force is enhanced, rather than suppressed, in the vicinity of the hole. This anti-screening effect is larger for a thinner, less massive disk with a smaller hole. At this stage, our setup is only of academic interest and its astrophysical consequences are unclear, but this result implies that the Vainshtein screening mechanism around less symmetric matter configurations are quite nontrivial.