Related papers: Wormhole on DGP brane
In the present paper we discuss properties of a model of a ring wormhole, recently proposed by Gibbons and Volkov. Such a wormhole connects two flat spacetimes which are glued through discs of the radius $a$ bounded by the string with…
We construct explicit examples of microstate geometries of four-dimensional black holes that lift to smooth horizon-free geometries in five dimensions. Solutions consist of half-BPS D-brane atoms distributed in $\mathbb{R}^3$. Charges and…
In this paper we derive new static phantom traversable wormholes by assuming a shape function with a quadratic dependence on the radial coordinate r. We mainly focus our study on wormholes sustained by exotic matter with positive energy…
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.
A new solution to Einstein equations in (1+5)-spacetime with an embedded (1+3) brane is given. This solution localizes the zero modes of all kinds of matter fields and 4-gravity on the (1+3) brane by an increasing, transverse gravitational…
Recently, traversable wormhole geometries were constructed in the context of f(R) gravity. The latter is equivalent to a Brans-Dicke theory with a coupling parameter w=0, which is apparently excluded from the narrow interval, -3/2<w<-4/3,…
In this paper, we introduce higher dimensional thin-shell wormholes in pure Gauss-Bonnet gravity. The focus is on thin-shell wormholes constructed by $N\geq5$-dimensional spherically symmetric vacuum solutions. The results suggest that,…
Static, spherically symmetric configurations of gravity with nonminimally coupled scalar fields are considered in D-dimensional space-times in the framework of generalized scalar-tensor theories. We seek special cases when the system has no…
Although wormholes can be treated as topological objects in spacetime and from a global point-of-view, a precise definition of what a wormhole throat is and where it can be located can be developed and treated entirely in terms of local…
The Dvali, Gabadadze and Porrati (DGP) model has a self-accelerating solution, the positive branch, where the brane is asymptotically de Sitter. A de Sitter space-time can be seen as a boundary between quintessence-like behaviour and…
In this article we study spherical thin-shell wormholes in five-dimensional Einstein-Gauss-Bonnet gravity. We show that configurations supported by non-exotic matter, that is matter satisfying the weak energy condition, are possible at the…
In brane-world cosmology gravitational waves can propagate in the higher dimensions (i.e., in the `bulk'). In some appropriate regimes the bulk gravitational waves may be approximated by plane waves. We systematically study five-dimensional…
In this work, wormholes, tunnel like structures introduced by Morris \& Thorne \cite{Morris95}, are explored within the framework of $f(R)$ gravity. Using the shape function $b(r)=r_0\big(\frac{r}{r_0}\big)^\gamma$, where $0<\gamma<1$, and…
In the context of brane-world models, we pursue the question of the existence of 5-dimensional solutions describing regular black holes localised close to the brane. Employing a perturbed Vaidya-type line-element embedded in a warped fifth…
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…
All the models of elementary particles and their interactions derived from String Theory involve a compact six-dimensional internal space. Its volume and shape should be fixed or stabilized, since otherwise massless scalar fields (moduli)…
We first briefly present a consistent world-volume Lagrangian description of lightlike p-branes (LL-branes) in two equivalent forms - a Polyakov-type and a dual to it Nambu-Goto-type formulations. The most important characteristic features…
Much work has been devoted to the phenomenology and cosmology of the so-called braneworld universe, where our (3+1)-dimensional universe lies on a brane surrounded by a (4+1)-dimensional bulk spacetime that is essentially empty except for a…
Starting with the D-dimensional Einstein-dilaton-antisymmetric form equations and assuming a block-diagonal form of a metric we derive a $(D-d)$-dimensional $\sigma$-model with the target space $SL(d,R)/SO(d) \times SL(2,R)/SO(2) \times R$…
In this work, we consider the possibility of expanding wormholes in higher-dimensions, which is an important ingredient of modern theories of fundamental physics. An important motivation is that non-trivial topological objects such as…