Ultrarelativistic spinning objects in nonlocal ghost-free gravity
Ultrarelativistic spinning objects in nonlocal ghost-free gravity
复制标题
非局域无鬼引力中的超相对论旋转物体
DOI：
10.1103/physrevd.101.124065
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发表时间：
2020
影响因子：
5
通讯作者：
V. Frolov
中科院分区：
文献类型：
--
作者：
Jens Boos;Jose Pinedo Soto;V. Frolov
我们在具有更高导数的修正引力理论中研究超相对论旋转物体（回旋体）的引力场。我们特别关注一类特殊的理论，它具有无限数量的导数，称为“无幽灵引力”，其中包括非局部形状因子，例如 $\exp(-\Box\ell^2)$，其中 $\ell$ 是非局部性的尺度。首先，我们获得静止旋转物体的线性化无重影方程的解。为了获得回转解决方案，我们提高了这些指标并采用了彭罗斯极限。这种方法使我们能够对任意数量的时空维度进行计算。所有解在回旋轴上都是规则的。在四个维度中，当尺度非局部性 $\ell$ 趋于零时，所获得的回旋解正确地再现了 Aichelburg--Sexl 度量及其对 Bonnor 早期发现的旋转源的推广。我们还研究了所获得的四维和更高维无鬼陀螺指标的性质，并简要讨论了它们可能的应用。
We study the gravitational field of ultrarelativistic spinning objects (gyratons) in a modified gravity theory with higher derivatives. In particular, we focus on a special class of such theories with an infinite number of derivatives known as "ghost-free gravity" that include a non-local form factor such as $\exp(-\Box\ell^2)$, where $\ell$ is the scale of non-locality. First, we obtain solutions of the linearized ghost-free equations for stationary spinning objects. To obtain gyraton solutions we boost these metrics and take their Penrose limit. This approach allows us to perform calculations for any number of spacetime dimensions. All solutions are regular at the gyraton axis. In four dimensions, when the scale non-locality $\ell$ tends to zero, the obtained gyraton solutions correctly reproduce the Aichelburg--Sexl metric and its generalization to spinning sources found earlier by Bonnor. We also study the properties of the obtained four-dimensional and higher-dimensional ghost-free gyraton metrics and briefly discuss their possible applications.