论文标题
加速螺母黑洞
Accelerating NUT black holes
论文作者
论文摘要
我们介绍并分析了一类精确的空间，这些空间描述了用螺母参数加速的黑洞。首先，我们验证CHNG，Mann和Stelea在2006年发现的复杂度量确实解决了爱因斯坦的真空场方程。我们明确计算Weyl张量的所有组件，并确定其代数结构。事实证明，它实际上是代数为I类型的I型，具有四个不同的主零方向。它解释了为什么在大型的D型SpaceTimes家族中没有（也找不到）这类解决方案（也找不到）。然后，我们将溶液转换为更方便的度量形式，该指标形式明确取决于三个物理参数：质量，加速度和螺母参数。这些参数可以独立设置为零，从而恢复了标准坐标中众所周知的空间，即C-Metric，Taub-Nut Metric，Schwarzschild Metric和Flat Minkowski空间。使用这种新的度量，我们研究了这种加速螺母黑洞的物理和几何特性。特别是，我们本地化并研究了四个杀戮视野（两个黑洞加两个加速度），并研究曲率。使用标量不变性，我们证明，每当螺母参数为非零时，都没有曲率奇点。我们确定渐近平坦的区域，并将它们与保形无限性联系起来。这导致了对全球结构的完全理解。增强旋转公制形式表明，实际上有一对黑洞。由于沿相应的两个轴旋转的宇宙弦或支撑杆的作用，它们在相反的方向上均匀加速。这些来源的旋转与螺母参数直接相关。在其附近，有病理区域具有闭合的时间曲线。
We present and analyze a class of exact spacetimes which describe accelerating black holes with a NUT parameter. First, we verify that the intricate metric found by Chng, Mann and Stelea in 2006 indeed solves Einstein's vacuum field equations of General Relativity. We explicitly calculate all components of the Weyl tensor and determine its algebraic structure. As it turns out, it is actually of algebraically general type I with four distinct principal null directions. It explains why this class of solutions has not been (and could not be) found within the large Plebanski-Demianski family of type D spacetimes. Then we transform the solution into a much more convenient metric form which explicitly depends on three physical parameters: mass, acceleration, and the NUT parameter. These parameters can independently be set to zero, recovering thus the well-known spacetimes in standard coordinates, namely the C-metric, the Taub-NUT metric, the Schwarzschild metric, and flat Minkowski space. Using this new metric, we investigate physical and geometrical properties of such accelerating NUT black holes. In particular, we localize and study four Killing horizons (two black-hole plus two acceleration) and investigate the curvature. Employing the scalar invariants we prove that there are no curvature singularities whenever the NUT parameter is nonzero. We identify asymptotically flat regions and relate them to conformal infinities. This leads to a complete understanding of the global structure. The boost-rotation metric form reveals that there is actually a pair of such black holes. They uniformly accelerate in opposite directions due to the action of rotating cosmic strings or struts located along the corresponding two axes. Rotation of these sources is directly related to the NUT parameter. In their vicinity there are pathological regions with closed timelike curves.
