相关论文: Wormhole Shadows
Black holes and wormholes are solutions of Einstein's field equations, both of which, from afar, look like a central mass. We show here that although at large distances both behave like Newtonian objects, close to the event horizon or to…
We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is…
By choosing an appropriate vielbein basis, we obtain a class of spherically-symmetric solutions in $f(T)$ gravities. The solutions are asymptotic to Minkowski spacetimes with leading falloffs the same as those of the Schwarzschild black…
A wormhole is a hypothetical tunnel through space. We employ the techniques taught in a standard calculus course to generate the images (embedding diagrams) of the Schwarzschild Wormhole and the Thorne-Morris Wormhole.
Shadows cast by the rotating black hole in perfect fluid matter are studied using analytical method. We consider three kinds of matter with standard equation of state in Cosmology: $-1/3$ (dark matter), 0 (dust) and $1/3$ (radiation). The…
We explore the possibility of traversable wormhole formation in the dark matter halos in the context of $f(Q)$ gravity. We obtain the exact wormhole solutions with anisotropic matter source based on the Bose-Einstein condensate,…
The analytic solution of the general relativity equations for spherically symmetric wormholes are given. We investigate the special case of a "traversable" wormhole i.e., one allowing the signal to pass through it. The energy-momentum…
We investigate the radial perturbations of Ellis-Bronnikov wormholes ($\mathrm{l}=0$) in a slowly rotating background expanded up to second order in rotation. We find indications that simple wormhole solutions such as Ellis-Bronnikov in…
Morris and Thorne developed wormhole solutions in the late 1980s when they discovered a recipe that wormholes must follow for travelers to cross them safely. They describe exotic matter as satisfying $-p_{r} > \rho$, where $p_{r}$ is the…
We show that the mass function method makes it much easier to obtain the exact solutions of Einstein equations. The known solutions for empty space and for the universe filled with dust-like matter are considered from the point of view of…
Solutions to Einstein's field equations describing rotating fluid bodies in equilibrium permit parametric (i.e. quasi-stationary) transitions to the extreme Kerr solution (outside the horizon). This has been shown analytically for discs of…
In general relativity, traversable wormholes are possible provided they do not represent shortcuts in the spacetime. Einstein equations, together with the achronal averaged null energy condition, demand to take longer for an observer to go…
The new dynamical solutions of Einstein's equations with perfect fluid in space-times with FLRW asymptotic behaviour, derived recently \cite{Cot,Cot1,Cot2}, may describe evaporating black holes whose masses dissipate into dust. The time…
We construct traversable wormholes with anti-de Sitter asymptotics supported by a phantom field. These wormholes are massless and symmetric with respect to reflection of the radial coordinate $\eta \to - \eta$. Their circumferential radius…
First, the ideas introduced in the wormhole research field since the work of Morris and Thorne are briefly reviewed, namely, the issues of energy conditions, wormhole construction, stability, time machines and astrophysical signatures.…
We construct models of two exotic objects: (i) a wormhole whose throat is hidden by a stellar object like a neutron star; and (ii) a wormhole inside a black hole. We work within Einstein's gravity coupled to two scalar fields with a…
Firstly, we review the pointwise and averaged energy conditions, the quantum inequality and the notion of the ``volume integral quantifier'', which provides a measure of the ``total amount'' of energy condition violating matter. Secondly,…
We investigate a new type of Schwarzschild wormhole, which relies on a 3-dimensional spacetime defect with degenerate metrics. This particular wormhole is a solution of the vacuum Einstein equations. We also study the generalized…
It has been argued that the recently detected ring-down gravity waveforms could be indicative only of the presence of light rings in a horizonless object, such as a surgical Schwarzschild wormhole, with the frequencies differing drastically…
We can survey an Ellis wormhole which is the simplest Morris-Thorne wormhole in our galaxy with microlensing. The light curve of a point source microlensed by the Ellis wormhole shows approximately $4\%$ demagnification while the total…