论文标题
4D爱因斯坦 - 高斯 - 尼特重力中的黑洞的准模式，稳定性和阴影
Quasinormal modes, stability and shadows of a black hole in the 4D Einstein-Gauss-Bonnet gravity
论文作者
论文摘要
最近，制定了一种$ d $维的正则化方法，导致非平凡$（3+1）$ - 尺寸的爱因斯坦 - 加斯 - 鲍尼斯（EGB）对重力的有效描述，据称是绕过Lovelock定理并避免了Ostrogragradsky的不稳定。后来证明，仅适用于某种广泛但有限的指标类别，而Aoki，Gorji和Mukohyama [Arxiv：2005.03859]才能表达出一种定义明确的四维EGB理论，从而破坏了Lorentz不变性在理论上一致的和经过观察的方式中。第一种幼稚方法的黑洞解决方案也证明是定义明确的理论的精确解决方案。在这里，我们计算标量，电磁和重力扰动的准模式，并找到带有高斯 - 骨网校正的球形对称和渐近平坦的黑色孔的阴影半径。我们表明，当（$ -16 m^2 <α\ Lessapprox 0.6 m^2 $）时，黑洞在重力上是稳定的。外部范围内的不稳定性是Eikonal的不稳定性，它以高多极的数量发展。阴影的半径$ r_ {sh} $以显着的精度遵守线性定律。
Recently a $D$-dimensional regularization approach leading to the non-trivial $(3+1)$-dimensional Einstein-Gauss-Bonnet (EGB) effective description of gravity was formulated which was claimed to bypass the Lovelock's theorem and avoid Ostrogradsky instability. Later it was shown that the regularization is possible only for some broad, but limited, class of metrics and Aoki, Gorji and Mukohyama [arXiv:2005.03859] formulated a well-defined four-dimensional EGB theory, which breaks the Lorentz invariance in a theoretically consistent and observationally viable way. The black-hole solution of the first naive approach proved out to be also the exact solution of the well-defined theory. Here we calculate quasinormal modes of scalar, electromagnetic and gravitational perturbations and find the radius of shadow for spherically symmetric and asymptotically flat black holes with Gauss-Bonnet corrections. We show that the black hole is gravitationally stable when ($-16 M^2<α\lessapprox 0.6 M^2$). The instability in the outer range is the eikonal one and it develops at high multipole numbers. The radius of the shadow $R_{Sh}$ obeys the linear law with a remarkable accuracy.
