相关论文: A Negative Mode About Euclidean Wormhole
We present a class of exact solutions in the framework of $2+1-$dimensional Einstein gravity coupled minimally to a doublet of scalar fields. Our solution can be interpreted upon tuning of parameters as an asymptotically flat wormhole as…
By assuming that only (i) bilocal vertex operators which are diagonal with respect to the basis for local field operators, and (ii) the convergent elements with nonzero positive energy of the density matrix representing the quantum state of…
A fundamental ingredient in wormhole physics is the presence of exotic matter, which involves the violation of the null energy condition. Although a plethora of wormhole solutions have been explored in the literature, it is useful to find…
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 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…
It has been claimed that wormholes are just as good a prediction of Einstein's theory as black holes, but they are subject to severe restrictions from quantum field theory. The purpose of this paper is to show that the claim can be…
We discuss new bounce-like (but non-time-reversal-invariant-) solutions to Euclidean equations of motion, which we dub boomerons. In the Euclidean path integral approach to quantum theories, boomerons make an imaginary contribution to the…
On the basis of exact solutions to the Einstein-Abelian gauge-dilaton equations in $D$-dimensional gravity, the properties of static axial configurations are discussed. Solutions free of curvature singularities are selected; they can be…
In this paper we review some properties for the evolving wormhole solution of Einstein equations coupled with nonlinear electrodynamics. We integrate the geodesic equations in the effective geometry obeyed by photons; we check out the weak…
In this work, we focus on the dynamics of a massive one-form field, \textbf{B}, often referred to simply as a vector field, that is minimally coupled to standard Einstein gravity. In the framework of four-dimensional spacetimes, the theory…
We investigate Euclidean wormholes in Gauss-Bonnet-dilaton gravity to explain the creation of the universe from nothing. We considered two types of dilaton couplings (i.e., the string-inspired model and the Gaussian model) and we obtained…
We investigate the quantum stability of a timelike topological wormhole with a simple geometry $M_2 \times S^2$, supported classically by anisotropic fluid. We compute the one-loop quantum backreaction generated by the vacuum fluctuations…
In this article, we study the possibility of sustaining a static and spherically symmetric traversable wormhole geometries admitting conformal motion in Einstein gravity, which presents a more systematic approach to search a relation…
The time evolution of the field perturbations in the wormhole and black bounce backgrounds are investigated. We find that the asymmetry of spacetime results in the asymmetry of the effective potential of the perturbed equation. The…
On this paper we consider the classical wormhole solution of the Born-Infeld scalar field. The corresponding classical wormhole solution can be obtained analytically for both very small and large $\dot{\phi}$. At the extreme limits of small…
Starting with a procedure for dealing with general asymptotic behaviors, we construct a quantum theory for asymptotically anti-de Sitter wormholes. We follow both the path integral formalism and the algebraic quantization program proposed…
We present new traversable wormhole and non-singular black hole solutions in pure, scale-free $R^2$ gravity. These exotic solutions require no null energy condition violating or "exotic" matter and are supported only by the vacuum of the…
A Morris-Thorne wormhole can only be sustained by violating the null energy condition, thereby requiring the existence of "exotic matter," a requirement that many researchers consider unphysical. Using a mostly qualitative approach, it is…
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…
In this work we demonstrate that wormholes can in principle be naturally created during the cosmological bounce without the need for the exotic matter or any kind of additional modifications of the gravitational sector, apart from the one…