Rotating cosmological cylindrical wormholes in GR and TEGR sourced by anisotropic fluids

Conformally symmetric traversable wormholes in modified teleparallel gravity

In this paper, we consider wormhole geometries in the context of teleparallel equivalent of general relativity (TEGR) as well as $f(T)$ gravity. The TEGR is an alternative geometrical formulation of Einstein's general relativity, where modified teleparallel gravity or $f(T)$ gravity has been invoked as an alternative approach for explaining an accelerated expansion of the universe. We present the analytical solutions under the assumption of spherical symmetry and the existence of a conformal Killing vectors to proceed a more systematic approach in searching for exact wormhole solutions. More p…

Wormhole solutions sourced by fluids, II: Three-fluid two-charged sources

Lack of a consistent metric for generating rotating wormholes motivates us to present a new one endowed with interesting physical and geometrical properties. When combined with the generalized method of superposition of fields, which consists in attaching a form of matter to each moving frame, it generates massive and charged (charge without charge) two-fluid-sourced, massive and two-charged three-fluid-sourced, rotating as well as new static wormholes which, otherwise, can hardly be derived by integration. If the lapse function of the static wormhole is bounded from above, no closed timelike …

$f({\sf R})$ Gravity Wormholes sourced by a Phantom Scalar Field

We derive an exact wormhole spacetime supported by a phantom scalar field in the context of $f({\sf R})$ gravity. Without specifying the form of the $f({\sf R})$ function, the scalar field self-interacts with a mass term potential that is derived from the scalar equation and the resulting $f({\sf R})$ model is purely supported by the scalar field and it is free of ghosts and avoids the tachyonic instability.

Wormhole solutions sourced by fluids, I: Two-fluid charged sources

We briefly discuss some of the known and new properties of rotating geometries that are relevant to this work. We generalize the analytical method of superposition of fields, known for generating nonrotating solutions, and apply it to construct massless and massive rotating physical wormholes sourced by a source-free electromagnetic field and an exotic fluid both anisotropic. Their stress-energy tensors are presented in compact and general forms. For the massive rotating wormholes there exists a mass-charge constraint yielding almost no more dragging effects than ordinary stars. There are coni…

圈量子宇宙学中由暗物质供源的可行走虫洞

Traversable Wormholes Sourced by Dark Matter in Loop Quantum Cosmology

本文在圈量子宇宙学中用各向同性暗物质构建可行走虫洞，分析三种密度分布并验证正则性、能量条件、奇异物质量及与M87观测对比的阴影特征。

由弦云提供源的 $f(R)$ 引力中的可穿越虫洞

Traversable wormholes in $f(R)$ gravity sourced by a cloud of strings

本文用两种途径研究弦云背景下简单 $f(R)$ 引力中的可穿越虫洞，结合 Padè 近似、场方程与数值分析检验形状函数、能量条件、稳定性和奇异物质，发现可违反 NEC 成洞但时空不稳定。