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相关论文: New Wormhole Solutions in a Viable $f(R)$ Gravity …

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We consider the evolution of traversable wormhole geometries in the inflationary, radiation -- and matter -- dominated eras, and dynamic wormholes with a traceless energy-momentum tensor (EMT), within the recently proposed {\it pole dark…

广义相对论与量子宇宙学 · 物理学 2021-02-01 Mahdi Kord Zangeneh , Francisco S. N. Lobo , Hooman Moradpour

We show that the violation of the null energy condition by matter, required by traversable wormholes, can be removed in spacetimes with torsion. In addition, we show that this violation can also be removed in the conformal frame obtained by…

广义相对论与量子宇宙学 · 物理学 2018-12-14 Fayçal Hammad , Étienne Massé , Patrick Labelle

A new framework is proposed for general dynamic wormholes, unifying them with black holes. Both are generically defined locally by outer trapping horizons, temporal for wormholes and spatial or null for black and white holes. Thus wormhole…

广义相对论与量子宇宙学 · 物理学 2009-10-31 Sean A. Hayward

This paper discusses the feasibility of thin-shell wormholes in spacetimes of embedding class one admitting a one-parameter group of conformal motions. It is shown that the surface energy density $\sigma$ is positive, while the surface…

广义相对论与量子宇宙学 · 物理学 2024-08-13 Peter K. F. Kuhfittig

It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the…

广义相对论与量子宇宙学 · 物理学 2014-11-20 Mubasher Jamil , Peter K. F. Kuhfittig , Farook Rahaman , Sk. A Rakib

In this study, we reach the equations of motion of Morris-Thorne wormhole geometry by means of the Einstein Field Equations and Klein-Gordon Equation of Scalar-Tensor theory by direct calculation. We discuss the anisotropic matter energy…

广义相对论与量子宇宙学 · 物理学 2018-07-19 Onur Genç

In this paper, we consider third order Lovelock gravity with a cosmological constant term in an n-dimensional spacetime $\mathcal{M}^{4}\times \mathcal{K}^{n-4}$, where $\mathcal{K}^{n-4} $ is a constant curvature space. We decompose the…

广义相对论与量子宇宙学 · 物理学 2015-12-23 Mahdi Kord Zangeneh , Francisco S. N. Lobo , Mohammad Hossein Dehghani

The paper deals with the static spherically symmetric wormhole solutions in $f(R)$-modified gravity theory with anisotropic matter field and for some particular choices for the shape functions. The present work may be considered as an…

广义相对论与量子宇宙学 · 物理学 2021-08-11 Bikram Ghosh , Saugata Mitra , Subenoy Chakraborty

We have proposed a novel shape function on which the metric that models traversable wormholes is dependent. Using this shape function, the energy conditions, equation of state and anisotropy parameter are analyzed in $f(R)$ gravity,…

广义相对论与量子宇宙学 · 物理学 2020-05-19 Gauranga C. Samanta , Nisha Godani , Kazuharu Bamba

In this talk I discuss pertinence of the wormholes to the problem of circumventing the light speed barrier and present a specific class of wormholes. The wormholes of this class are static and have arbitrarily wide throats, which makes them…

广义相对论与量子宇宙学 · 物理学 2007-05-23 S. V. Krasnikov

The present paper is aimed at the study of traversable wormholes in $f(R)$ gravity with a viable $f(R)$ function defined as $f(R)=R-\mu R_c\Big(\frac{R}{R_c}\Big)^p$, where $R$ is scalar curvature, $\mu$, $R_c$ and $p$ are constants with…

广义相对论与量子宇宙学 · 物理学 2020-05-06 Nisha Godani , Gauranga C. Samanta

It has been suggested that the cosmological constant is a variable dynamical quantity. A class of solution has been presented for the spherically symmetric space time describing wormholes by assuming the erstwhile cosmological constant…

广义相对论与量子宇宙学 · 物理学 2008-11-26 F. Rahaman , M. Kalam , M. Sarker , A. Ghosh , B. Raychaudhuri

Traversable wormholes necessarily require violations of the averaged null energy condition; this being the definition of ``exotic matter''. However, the theorems which guarantee the energy condition violation are remarkably silent when it…

广义相对论与量子宇宙学 · 物理学 2011-07-18 Matt Visser , Sayan Kar , Naresh Dadhich

In this work, we investigate the existence of wormholes within the framework of Loop Quantum Cosmology, using isotropic dark matter as the source. We analyze three distinct density profiles and solve the modified gravity field equations…

广义相对论与量子宇宙学 · 物理学 2025-04-11 Marcos V. de S. Silva , G. Alencar , R. N. Costa Filho , R. M. P. Neves , Celio R. Muniz

A fundamental property in wormhole physics is the flaring-out condition of the throat, which through the Einstein field equation entails the violation of the null energy condition. In the context of modified theories of gravity, it has also…

广义相对论与量子宇宙学 · 物理学 2012-11-07 Francisco S. N. Lobo

We present the first analysis of traversable wormhole solutions within the framework of Einstein-aether theory. We show that the corresponding field equations admit three distinct wormhole geometries, obtained by adopting three different…

广义相对论与量子宇宙学 · 物理学 2026-04-01 Hanif Golchin , Hamid R. Bakhtiarizadeh , Mohammad Reza Mehdizadeh

This thesis investigates traversable wormhole spacetimes in modified theories of gravity, where the matter at the wormhole throat is described by an anisotropic energy-momentum tensor. Wormhole solutions are constructed in the context of…

广义相对论与量子宇宙学 · 物理学 2025-04-15 Zinnat Hassan

We obtain a large class of Lorentzian wormhole spacetimes in scalar-tensor gravity, for which the matter stress energy does satisfy the weak energy condition. Our constructions have zero Ricci scalar and an everywhere finite, non-zero…

广义相对论与量子宇宙学 · 物理学 2016-07-12 Rajibul Shaikh , Sayan Kar

In this work, the study of traversable wormholes in $f(R)$-massive gravity with the function $f(R)=R+\alpha_{1} R^{n}$, where $\alpha_{1}$ and $n$ are arbitrary constants, is considered. We choose the modified shape function $b(r)$. We…

广义相对论与量子宇宙学 · 物理学 2020-10-14 Takol Tangphati , Auttakit Chatrabhuti , Daris Samart , Phongpichit Channuie

In the present work, we seek for static spherically symmetric solutions representing wormhole configurations in generalized Rastall gravity (GRG). In this theory, a varying coupling parameter could act as dark energy (DE) and thus, it can…

广义相对论与量子宇宙学 · 物理学 2025-04-08 Naser Sadeghnezhad