相关论文: Brans-Dicke Wormhole Revisited -- II
We investigate the possibility of obtaining traversable wormholes supported by phantom scalar fields in Lorentz-violating gravity with an antisymmetric rank-2 tensor with a non-zero vacuum expectation value non-minimally coupled to the…
We present the first results of a self-consistent solution of the semiclassical Einstein field equations corresponding to a Lorentzian wormhole coupled to a quantum scalar field. The specific solution presented here represents a wormhole…
Static axisymmetric thin-shell wormholes are constructed within the framework of the Brans-Dicke scalar-tensor theory of gravity. Examples of wormholes associated with vacuum and electromagnetic fields are studied. All constructions must be…
There are a number of reasons to study wormholes with generic cosmological constant $\Lambda$. Recent observations indicate that present accelerating expansion of the universe demands $\Lambda>0$. On the other hand, some extended theories…
The ring wormhole is the zero-mass limit of the Kerr metric. Its geometry is locally flat, but the topology is nontrivial, with a throat connecting two asymptotic regions and a distributional curvature singularity on the ring encircling the…
The C-metric in vacuum general relativity describes a pair of accelerated black holes supported by conical singularity. In this paper, we present a new family of exact solutions to the Einstein-phantom scalar system that describes…
We obtain new black hole solutions in a Einstein-Bumblebee-scalar theory. By starting with a Einstein-Bumblebee theory in D + d dimensions, the scalar dilaton field and its interaction with the gravitational and bumblebee fields are…
We find static spherically symmetric solutions of scale invariant $R^2$ gravity. The latter has been shown to be equivalent to General Relativity with a positive cosmological constant and a scalar mode. Therefore, one expects that solutions…
A phase space is built that allows to study, classify and compare easily large classes of static spherically symmetric wormholes solutions, sustained by an isotropic perfect fluid in General Relativity. We determine the possible locations…
Using a new ansatz for solving the Einstein equations with a scalar field with the sign of the kinetic term inverted, I find a series of formulae to derive axial symmetric stationary exact solutions of the Phantom scalar field in general…
In recent, Kar.S et.al [ Phys Rev D 67,044005 (2003) ] have obtained static spherically symmetric solutions of the Einstein-Kalb-Ramond field equations. We have shown that their solutions, indeed, represent Wormholes.
We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported…
Since the Brans-Dicke theory is conformal related to the dilaton gravity theory, by applying a conformal transformation to the dilaton gravity theory, we derived the cosmological constant term in the Brans-Dicke theory and the physical…
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…
Wormhole solutions to the equations of general relativity have some spectacular local and global properties. As these unusual features are not explicitly forbidden by known physics, wormholes are considered in various astrophysical and…
We seek wormholes among rotating cylindrically symmetric configurations in general relativity. Exact wormhole solutions are presented with such sources of gravity as a massless scalar field, a cosmological constant, and a scalar field with…
In certain extensions of General Relativity, wormholes generated by spherically symmetric electric fields can resolve black hole singularities without necessarily removing curvature divergences. This is shown by studying geodesic…
To date, many exotic predictions of Einstein's equations have been corroborated, with one exception: wormholes (WHs). In this work, we analyse a new exact solution combination to the Einstein-Maxwell-Dilaton or Phantom equations, which…
An explicit Robinson--Trautman solution with minimally coupled free scalar field was derived and analyzed recently. It was shown that this solution possesses a curvature singularity which is initially naked but later enveloped by a horizon.…
A lower bound on the size of a Lorentzian wormhole can be obtained by semiclassically introducing the Planck cut-off on the magnitude of tidal forces (Horowitz-Ross constraint). Also, an upper bound is provided by the quantum field…