论文标题
物质的剪切和涡度在同型平坦的空间中
Matter shear and vorticity in conformally flat spacetimes
论文作者
论文摘要
在本文中，我们考虑了弗里德曼·莱梅特尔·罗伯逊·沃克（FLRW）时期包含一般物质领域的同型扰动。使用线性化的场方程，我们在没有任何由Weyl曲率供电的自由重力的情况下，发掘了物质剪切和涡度的一些重要几何特性，以及它们如何与热力学量相互作用。由于几乎没有任何物理逼真的旋转精确的同型扁平解决方案，因此这些协方差和规格不变的结果透明地透明了涡度在线性化方案中的作用。最有趣的是，我们证明了此物质剪切遵守横向无纹状张量波方程，并且涡度服从该制度中的矢量波方程。这些剪切和涡度波代替了引力波，因为它们在因果关系中携带有关这些空间曲率中局部变化的信息。
In this paper we consider conformally flat perturbations on the Friedmann Lemaitre Robertson Walker (FLRW) spacetime containing a general matter field. Working with the linearised field equations, we unearth some important geometrical properties of matter shear and vorticity and how they interact with the thermodynamical quantities in the absence of any free gravity powered by the Weyl curvature. As there are hardly any physically realistic rotating exact conformally flat solutions in general relativity, these covariant and gauge invariant results bring out transparently the role of vorticity in the linearised regime. Most interestingly, we demonstrate that the matter shear obeys a transverse traceless tensor wave equation, and the vorticity obeys a vector wave equation in this regime. These shear and vorticity waves replace the gravitational waves in the sense that they causally carry the information about local change in the curvature of these spacetimes.
