Related papers: Cosmological wormholes
Wormholes can be described as geometrical structures in space and time that can serve as connection between distant regions of the universe. Mathematically, general wormholes can be defined both on stationary as well as on dynamic line…
Noether symmetry has been invoked to explore the forms of a couple of coupling parameters and the potential appearing in a general scalar-tensor theory of gravity in the background of Robertson-Walker space-time. Exact solutions of…
We argue that one can nucleate a traversable wormhole via a nonperturbative process in quantum gravity. To support this, we construct spacetimes in which there are instantons giving a finite probability for a test cosmic string to break and…
In this work, we introduce a novel set of asymptotically flat wormhole solutions within the framework of $f(R,T)$ theory of gravity. Considering a linear $f(R,T)=R+ 2\lambda T$ form, we show that a wide variety of wormhole solutions with…
We study the properties of evolving wormholes able to exist in a closed Friedmann dust-filled universe and described by a particular branch of the well-known Lema{\i}tre-Tolman-Bondi solution to the Einstein equations and its generalization…
We study thermodynamics of dynamical traversable wormholes. These wormholes are investigated in the background of different cosmological models, with and without the cosmological constant, and which include the power-law and exponential…
A spherically symmetric wormhole in Newtonian gravitation in curved space, enhanced with a connection between the mass density and the Ricci scalar, is presented. The wormhole, consisting of two connected asymptotically flat regions,…
The present work deals with a spherically symmetric space-time which is asymptotically (at spatial infinity) FRW space-time and represents wormhole configuration: The matter component is divided into two parts--(a) dissipative but…
We obtain a family of regular static, spherically symmetric solutions in Einstein--Cartan theory with an electromagnetic field and a nonminimally coupled scalar field with the correct sign of kinetic energy density. At different values of…
The gargantuan discrepancy between the value of the observed cosmological constant and that expected from the zero-point energy of known matter fields can be eliminated by supposing that on macroscopic scales the overwhelming majority of…
An intriguing solution that appears in General Relativity (GR) but has not been observed so far is the wormhole. This exotic solution describes a topological bridge connecting two distinct universes or two different points in the same…
We present the simplest topological classification of wormholes and demonstrate that in open Friedmann models the genus $n\geq 1$ wormholes are stable and do not require the presence of exotic forms of matter, or any modification of general…
Given an anisotropic fluid source, we determine in closed forms, upon solving the field equations of general relativity (GR) and teleparallel gravity (TEGR) coupled to a cosmological constant, cylindrically symmetric four-dimensional…
Within 2+1-dimensional cosmological new massive gravity, we consider thin-shell and thin-shell wormhole construction. For this, we introduce first, the junction conditions apt for the fourth order terms in the action of the theory. Then, by…
The purpose of this paper is to show that wormholes in noncommutative geometry can be macroscopic, based in part on an earlier study. The necessary violation of the weak energy condition is attributable to the noncommutative-geometry…
A spherically symmetric space-time solution for a diffusive two measures theory is studied. An asymmetric wormhole geometry is obtained where the metric coefficients have a linear term for galactic distances and the analysis of Mannheim and…
We study a solution of Einstein's equations that describes a straight cosmic string with a variable angular deficit, starting with a $2 \pi$ deficit at the core. We show that the coordinate singularity associated to this defect can be…
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…
We have examined the possible construction of a stationary, spherically symmetric and spatially inhomogeneous wormhole spacetime supported by the phantom energy. The later is supposed to be represented by the modified Chaplygin gas equation…
We construct an eternal traversable wormhole connecting two asymptotically $\text{AdS}_4$ regions. The wormhole is dual to the ground state of a system of two identical holographic CFT's coupled via a single low-dimension operator. The…