相关论文: Cosmological wormholes
We have recently discovered a smooth vacuum-wormhole solution of the first-order equations of general relativity. Here, we obtain the corresponding multiple-vacuum-wormhole solution. Assuming that our world is essentially Minkowski…
We describe the analytical extension of certain static cylindrical multi--cosmic string metrics to wormhole spacetimes with only one region at spatial infinity, and investigate in detail the geometry of asymptotically Minkowskian wormhole…
We find a new exact solution to Einstein field equations that represents a cosmological wormhole embedded in a flat Friedmann-Lema\^itre-Robertson-Walker universe. The new metric is a generalization of a previous cosmological wormhole…
A new cosmological object in analogy with the concept of a wormhole in general relativity is introduced. As wormholes connect two distant points through a tunnel in spacetime, this new object connects two spacetime through a large mouth…
Embedding theorems, which have a long history in the general theory of relativity, are used in this paper to account for two of the most troubling aspects of Morris-Thorne wormholes, (1) the origin of exotic matter and the amount needed to…
In this paper, we construct an evolving wormhole in the dark matter halo. This work is relevant since matter has two components: (i) cosmological part (only time-dependent) and (ii) wormhole part (only space-dependent). In order to…
In this article, we construct a family of spherically symmetric thin-shell wormholes within scalar-tensor theories of gravity. In the case of wormholes symmetric across the throat, we study the matter content and analyze the stability of…
In this article, we construct a class of constant curvature and spherically symmetric thin-shell Lorentzian wormholes in F(R) theories of gravity and we analyze their stability under perturbations preserving the symmetry. We find that the…
We study spherically symmetric, self-similar wormhole solutions supported by colliding streams of negative-energy null dust, and their dynamical formation. Under the assumption of self-similarity, the Einstein equations reduce to a system…
Analytical wormhole solutions in Brans-Dicke theory in the presence of matter are presented. It is shown that the wormhole throat must not be necessarily threaded with exotic matter.
Recently we solved the Einstein's field equations to obtain the exact solution of the cosmological model with the Morris-Thorne type wormhole. We found the apparent horizons and analyzed their geometric natures, including the causal…
Ghost stars are compact configurations characterized by an arbitrarily small total mass. Such objects require regions of negative energy density -a condition typically regarded as unphysical within the context of conventional stellar…
The aim of the present paper is two-fold. First we describe the Lagrangian dynamics of a recently proposed new class of lightlike p-branes and their interactions with bulk space-time gravity and electromagnetism in a self-consistent manner.…
While in general relativity black holes can be freely embedded into a cosmological background, the same problem in brane-worlds is much more cumbersome. We present here the results obtained so far in the explicit constructions of such…
We construct a 2+1 dimensional spacetime of constant curvature whose spatial topology is that of a torus with one asymptotic region attached. It is also a black hole whose event horizon spins with respect to infinity. An observer entering…
In this paper, we introduce the $n$-dimensional Lorentzian wormhole solutions of third order Lovelock gravity. In contrast to Einstein gravity and as in the case of Gauss-Bonnet gravity, we find that the wormhole throat radius, $r_0$, has a…
In this work, we derive an exact vacuum solution to the Einstein field equations that depends on three constant parameters: the throat radius $r_0$, a parameter $q$, which is closely associated with the Komar mass, and a parameter $s$,…
In this work, we explore the possibility that static and spherically symmetric traversable wormhole geometries are supported by modified teleparallel gravity or f(T) gravity, where T is the torsion scalar. Considering the field equations…
Wormholes are hypothetical tunnels that connect remote parts of spacetime. In General Relativity, wormholes are threaded by exotic matter that violates the energy conditions. In this work, we consider wormholes threaded by nonexotic matter…
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…