Related papers: Volume Integral Theorem for Exotic Matter
In this paper, we explore wormhole solutions in a higher-derivative theory of gravity where the action depends not only on the Ricci scalar \(R\), but also on its d'Alembertian, \(\Box R\). Such \(f(R,\Box R)\) models are motivated by…
In this study, we investigate traversable wormholes within the framework of Einstein-Euler-Heisenberg (EEH) nonlinear electrodynamics. By employing the Einstein field equations with quantum corrections from the Euler-Heisenberg Lagrangian,…
To find more deliberate $f(R, T)$ astrophysical solutions, we proceed by studying wormhole geometries under the assumption of spherical symmetry and the existence of a conformal Killing symmetry to attain the more acceptable astrophysical…
We propose a new notion of singularity in General Relativity which complements the usual notions of geodesic incompleteness and curvature singularities. Concretely, we say that a spacetime has a volume singularity if there exist points…
Spherically symmetric thin-shell wormholes are studied within the framework of Einstein-Born-Infeld theory. We analyze the exotic matter content and find that for certain values of the Born-Infeld parameter the amount of exotic matter on…
We discuss the relevance of quantum gravity to the frontier questions in high energy phenomenology: the problems of dark matter, dark energy, and vacuum selection as well as the problems of emergent spacetime and wormholes. Dark matter and…
This work presents a new wormhole solution in General Relativity supported by the quantum vacuum fluctuations of the Casimir effect between perfect chromometallic mirrors in $(3+1)$ dimensions, which was recently fitted using…
We numerically construct a symmetric wormhole solution in pure Einstein gravity supported by a massive $3$-form field with a potential that contains a quartic self-interaction term. The wormhole spacetimes have only a single throat and they…
It is well known that phantom energy, which is characterized by the equation of state $p=\omega\rho$, $\omega <-1$, can support Morris-Thorne wormholes since it leads to a violation of the null energy condition. The purpose of this note is…
It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the…
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…
We investigate wormhole solutions using the modified gravity model $f(Q,T)$ with viscosity and aim to find a solution for the existence of wormholes mathematically without violating the energy conditions. We show that there is no need to…
We consider rotating wormhole solutions in general relativity supported by a complex non-phantom spinor field (which provides a nontrivial spacetime topology) and electromagnetic fields. The solutions are asymmetric, regular, asymptotically…
Traversable wormholes (TWHs) remain one of the most intriguing predictions of General Relativity (GR), offering passage through space-time. However, their existence requires the violation of the null energy condition, making their detection…
Spacetime wormholes are evidently an essential component of the construction of a time machine. Within the context of general relativity, such objects require, for their formation, exotic matter -- matter that violates at least one of the…
The generalization of Birkhoff's theorem for higher dimensions in Lovelock gravity permits us to investigate the black hole solutions with horizon geometries of nonconstant curvature. We present a new class of exotic dyonic black holes in…
We show that Lorentzian (traversable) wormholes and time machines with semi-classical spacetimes are unstable due to their violation of the null energy condition (NEC). Semi-classicality of the energy-momentum tensor in a given quantum…
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…
The intrinsic non-perturbative features of string-theoretic corrections, particularly those arising from T-duality, have been shown to naturally introduce an effective ultraviolet (UV) cutoff into the gravitational framework. This cutoff,…
Wormholes that meet the flare-out condition violate the weak energy condition in classical general relativity. The purpose of this note is to show that even a slight modification of the gravitational theory could, under certain conditions,…