论文标题
painleve-gullstrand形式的闪光时空的形式
Painleve-Gullstrand form of the Lense-Thirring spacetime
论文作者
论文摘要
标准的晶状度度量是一个世纪以上的慢速慢速近距离近似，仅取决于旋转巨大体内的重力场，仅取决于源的总质量和角动量。尽管它不是对真空爱因斯坦方程式的精确解决方案，但渐近地刺激性度量可以在大距离内接近Kerr公制。在本文中，我们将讨论标准晶状体标准的特定变体，以简单性，清晰度和各种形式的“改善”行为（在文章正文中更仔细地定义）。特别是，我们将构建一个明确的单位painleve-gullstrand变体，该变体具有平坦的空间切片，非常简单且物理直观的四分法和非常简单的曲率张量。我们将验证透明的时空的这种变体是彼得罗夫I型（因此它不是代数特别的），但是仍然具有一些非常直接的时间般的测量学（“雨水”的大地测量学）。我们还将讨论轴向和赤道大地测量学，ISCOS和圆形光子轨道。最后，我们通过讨论一些天体物理相关的估计来结束，并分析如果我们推断为r值的小值会发生什么。
The standard Lense-Thirring metric is a century-old slow-rotation large-distance approximation to the gravitational field outside a rotating massive body, depending only on the total mass and angular momentum of the source. Although it is not an exact solution to the vacuum Einstein equations, asymptotically the Lense-Thirring metric approaches the Kerr metric at large distances. Herein we shall discuss a specific variant of the standard Lense-Thirring metric, carefully chosen for simplicity, clarity, and various forms of "improved" behaviour, (to be more carefully defined in the body of the article). In particular we shall construct an explicit unit-lapse Painleve-Gullstrand variant of the Lense-Thirring spacetime, that has flat spatial slices, a very simple and physically intuitive tetrad, and extremely simple curvature tensors. We shall verify that this variant of the Lense-Thirring spacetime is Petrov type I, (so it is not algebraically special), but nevertheless possesses some very straightforward timelike geodesics, (the "rain" geodesics). We shall also discuss on-axis and equatorial geodesics, ISCOs and circular photon orbits. Finally, we wrap up by discussing some astrophysically relevant estimates, and analyze what happens if we extrapolate down to small values of r.
