Related papers: Wormholes from Averaging over States

Primordial black holes may have formed in the radiative era of the early Universe from the collapse of large enough amplitude perturbations of the metric. These correspond to non linear energy density perturbations characterized by an…

We derive and critically examine the consequences that follow from the formation of a regular black or white hole horizon in finite time of a distant observer. In spherical symmetry, only two distinct classes of solutions to the…

We introduce the notion of fluid approximation of a quantum spherical black hole in the context of Loop Quantum Gravity. In this limit, the microstates of the black hole are intertwiners between "large" representations $s_i$ which typically…

In the semiclassical treatment of gravity, an external observer can measure only the mean (not the exact) mass of the black hole (BH). By contrast, in fully quantum gravity the exact (not only mean) BH mass is measurable by the external…

We study quantum mechanically the self-similar black hole formation by collapsing scalar field and find the wave functions that give the correct semiclassical limit. In contrast to classical theory, the wave functions for the black hole…

We study "half-wormhole-like" saddle point contributions to spectral correlators in a variety of ensemble average models, including various statistical models, generalized 0d SYK models, 1d Brownian SYK models and an extension of it. In…

Using the Hartle-Hawking no-boundary proposal for the wave function of the universe, we can study the wave function and probability of a single black hole created at the birth of the universe. The black hole originates from a constrained…

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…

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…

We treat two aspects of the physics of stationary black holes. First we prove that the proportionality, d(energy) ~ d(area) for arbitrary perturbations (``extended first law''), follows directly from an extremality theorem drawn from…

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…

The presence of a horizon is the principal marker for black holes as they appear in the classical theory of gravity. In General Relativity (GR), horizons have several defining properties. First, there exists a static spherically symmetric…

Starting from a quantization relation for primordial black holes, it is shown that quantum fluctuations can play a fundamental role in determining the effective scales of self-gravitating astrophysical systems. Furthermore the…

It is the goal of this thesis to revisit and revise the problem of black hole formation and evolution in semiclassical gravity -- a theory in which spacetime is treated classically, while matter admits a quantum description, coupling to…

One would expect spacetime to have a foam-like structure on the Planck scale with a very high topology. If spacetime is simply connected (which is assumed in this paper), the non-trivial homology occurs in dimension two, and spacetime can…

We explore the quantum nature of black holes by introducing an effective framework that takes into account deviations from the classical results. The approach is based on introducing quantum corrections to the classical Schwarzschild…

The idea that quantum gravity effects might leak outside the horizon of a black hole has recently been intensively considered. In this study, we calculate the quasinormal modes as a function of the location and amplitude of a generic metric…

In semiclassical gravity, the final state of black-hole evaporation cannot be described by a pure state. Nevertheless, we point out that the system can be described by a generalized pure state, which is not defined on a 3-dimensional…

We discuss some arguments in favour of the proposal that the quantum correlations contained in the pure state-vector evolving according to Schoedinger equation can be eliminated by the action of multiply connected wormholes during…

In this work, we find exact wormhole solutions in the context of noncommutative geometry, and further explore their physical properties and characteristics. The energy density of these wormhole geometries is a smeared and particle-like…