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arXiv 1903.09862gr-qc
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圆柱形虫洞:在GR中寻找可行的无幻象模型

Cylindrical wormholes: a search for viable phantom-free models in GR

K. A. Bronnikov, S. V. Bolokhov, M. V. Skvortsova

摘要:

在广义相对论(GR)中,众所周知的虫洞问题是需要奇异物质来支撑它们,这违反了弱能量条件(WEC)。这个问题看起来更容易,如果不是岛状的配置,考虑弦状的,其中包括旋转的圆柱对称时空。然而,对于圆柱形虫洞的解决方案,一个问题是缺乏渐近平坦性,这使得它不可能在我们的宇宙中观察到它们的入口。有人建议通过在喉道不同侧的某些表面$Σ_-$和$Σ_+$处将虫洞解加入到平坦渐近区域来解决这个问题。该构型由三个区域组成,内部区域包含喉部和两个平坦的外部区域。我们讨论了不同种类的源物质适合于描述这种模型的内部区域(标量场,各向同性和各向异性流体),并提出了两个例子,其中内部物质本身和两个交界面上的表面物质$Σ_\pm$尊重WEC。其中一种模型的内部源是压力等于其能量密度的刚性理想流体,另一种模型的内部源是一种特殊的各向异性流体。这两种模型都没有封闭的时间型曲线。因此,我们得到的例子,经常两次渐近平坦的虫洞模型在GR没有外来物质,没有因果关系违反。

英文摘要:

The well-known problem of wormholes in general relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one considers string-like ones, among them, cylindrically symmetric space-times with rotation. However, for cylindrical wormhole solutions a problem is the lacking asymptotic flatness, making it impossible to observe their entrances as local objects in our Universe. It was suggested to solve this problem by joining a wormhole solution to flat asymptotic regions at some surfaces $Σ_-$ and $Σ_+$ on different sides of the throat. The configuration then consists of three regions, the internal one containing a throat and two flat external ones. We discuss different kinds of source matter suitable for describing the internal regions of such models (scalar fields, isotropic and anisotropic fluids) and present two examples where the internal matter itself and the surface matter on both junction surfaces $Σ_\pm$ respect the WEC. In one of these models the internal source is a stiff perfect fluid whose pressure is equal to its energy density, in the other it is a special kind of anisotropic fluid. Both models are free from closed timelike curves. We thus obtain examples of regular twice asymptotically flat wormhole models in GR without exotic matter and without causality violations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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