$f(R)$引力理论的含时虫洞解和能量条件

$f(R)$引力中的圆柱薄壳虫洞

Cylindrical Thin-shell Wormholes in $f(R)$ gravity

本文利用剪切粘贴方法构造了带$f(R)$项的带电黑弦薄壳虫洞。我们把$f(R)$模型看作是虫洞喉部的奇异物质源。在$R+δR^2$模型的背景下，分析了径向扰动下相应解的稳定性。结果表明，对于不同的$δ$值，稳定解和不稳定解都存在.在$δ{\rightarrow}0$极限下，所有结果都归结为广义相对论.

Existence of stable wormholes on a noncommutative-geometric background in modified gravity

In this paper, we discuss spherically symmetric wormhole solutions in $f(R,T)$ modified theory of gravity by introducing well-known non-commutative geometry in terms of Gaussian and Lorentizian distributions of string theory. For some analytic discussion, we consider an interesting model of $f(R,T)$ gravity defined by $f(R,T)=f_{1}(R)+λT$. By taking two different choices for the function $f_{1}(R)$, that is, $f_{1}(R)=R$ and $f_{1}(R)=R+αR^{2}+γR^{n}$, we discuss the possible existence of wormhole solutions. In the presence of non-commutative Gaussian and Lorentizian distributions, we get exac…

Noncommutative Wormhole Solutions in Einstein Gauss-Bonnet Gravity

In this paper, we explore static spherically symmetric wormhole solutions in the framework of $n$-dimensional Einstein Gauss-Bonnet gravity. Our objective is to find out wormhole solutions that satisfy energy conditions. For this purpose, we consider two frameworks such as Gaussian distributed and Lorentzian distributed non-commutative geometry. Taking into account constant redshift function, we obtain solutions in the form of shape function. The fifth and sixth dimensional solutions with positive as well as negative Gauss-Bonnet coefficient are discussed. Also, we check the equilibrium condit…

Quantum Gravity Wormholes and Topological Teleporter

The question of a possibility of opening a wormhole due to the deformation of the equation of state of the matter caused by quantum gravity effects is considered. As a wormhole environment, the previously considered model of a galaxy with radial flows of dark matter is selected. The calculation shows, that for a wormhole solution in the framework of this model, after the nominal classical density exceeds a critical value in the Planck range, the components of the energy-momentum tensor become negative in a certain order. First, the mass density becomes negative, then the radial pressure, then …

Probing the existence of the ZTF Casimir wormholes in the framework of $f(\mathcal{R})$ gravity

For the spherically symmetric static traversable wormholes, supported by the Casimir energy in $f(\mathcal{R})=\mathcal{R}+α\mathcal{R}^2$ Quadratic, $f(\mathcal{R})=f_0 \mathcal{R}^n$ power-law Modified Gravity (MOG) theories we investigate energy conditions and dynamical stability of the wormhole solutions. Especially, we study Zero Tidal Forces (ZTF) Casimir WH's with anisotropic fluid located at the throat. By using the Casimir energy density and modified Einstein Field Equations (EFE's) we derived suitable shape functions for each modified gravity of our consideration. The stability of Ca…

Traversable wormholes with logarithmic shape function in f(R, T) gravity

In the present work, a new form of the logarithmic shape function is proposed for the linear $f(R,T)$ gravity, $f(R,T)=R+2λT$ where $λ$ is an arbitrary coupling constant, in wormhole geometry. The desired logarithmic shape function accomplishes all necessary conditions for traversable and asymptotically flat wormholes. The obtained wormhole solutions are analyzed from the energy conditions for different values of $λ$. It has been observed that our proposed shape function for the linear form of $f(R,T)$ gravity, represents the existence of exotic matter and non-exotic matter. Moreover, for $λ=0…

引力彩虹和可穿越的虫洞

Gravity's Rainbow and Traversable Wormholes

在引力彩虹的背景下，考虑状态方程$p_{r} = ωρ$，计算了可穿越虫洞背景下引力子单圈对经典能量的贡献。调查评估通过高斯试探波泛函的变分方法。然而，我们没有使用正则化/重整化过程，而是使用引力彩虹引起的扭曲来处理发散。