Related papers: Firewalls from wormholes in higher genus
Almheiri, Marolf, Polchinski, and Sully, recently claimed that once a black hole has radiated more than half its initial entropy (the Page time), the horizon is replaced by a "firewall" at which infalling observers burn up, in apparent…
The central challenge in trying to resolve the firewall paradox is to identify excitations in the near-horizon zone of a black hole that can carry information without injuring a freely falling observer. By analyzing the problem from the…
The notion of antipodal identification on the black hole horizon is further explained and elaborated. Contrasting with numerous attempts in the literature to make fuzzy, poorly motivated models for black holes, we explain how, with an…
Using the result obtained in a prevoius paper, in which I found an upper limit on the region of particle creation in the vicinity of the event horizon of a Schwarzschild black hole, and by assuming that all the created energy will be…
Evidence to the case that classical gravitation provides the clue to make sense out of quantum gravity is presented. The key observation is the existence in classical gravitation of child universe solutions or "almost" solutions, "almost"…
We investigate higher dimensional cosmological models in the semiclassical approximation with Hartle-Hawking Boundary conditions, assuming a gravitational action which is described by the scalar curvature with a cosmological constant. In…
We present calculations indicating the possibility of a new class of Type I supernovae. In this new paradigm relativistic terms enhance the self gravity of a carbon-oxygen white dwarf as it passes or orbits near a black hole. This…
It has been claimed that extreme black holes exhibit a phenomenon of flux expulsion for abelian Higgs vortices, irrespective of the relative width of the vortex to the black hole. Recent work by two of the authors showed a subtlety in the…
In this note we point out that primordial black holes could be much shorter lived than usually assumed if there is a large hidden sector of particles that only interacts gravitationally with the particles of the standard model. The…
An earlier study [Rahaman et al. (2014) & Kuhfittig (2014)] has demonstrated the possible existence of wormholes in the outer regions of the galactic halo, based on the Navarro-Frenk-White (NFW) density profile. This paper uses the…
In an approach to quantum gravity where space-time arises from coarse graining of fundamentally discrete structures, black hole formation and subsequent evaporation can be described by a unitary evolution without the problems encountered by…
First results of a numerical investigation of primordial black hole formation in the radiation dominated phase of the Early Universe are presented. The simulations follow the gravitational collapse of three different families of…
Non-perturbative quantum gravity effects might allow a black-to-white hole transition. We revisit this increasingly popular hypothesis by taking into account the fundamentally random nature of the bouncing time. We show that if the…
Quantization of the gravitational field may allow the existence of a decay channel of black holes into white holes with an explicit time-reversal symmetry. The definition of a meaningful decay probability for this channel is studied in…
Several processes in the early universe might lead to the formation of primordial black holes with different masses. These black holes would interact with the cosmic plasma through accretion and emission processes. Such interactions might…
A new scenario for the emission of high-energy gamma-rays from dark matter annihilation around massive black holes is presented. A black hole can leave its parent halo, by means of gravitational radiation recoil, in a merger event or in the…
A general formulation of the basic conflict of the information problem is given, encapsulated in a "black hole theorem." This is framed in a more general context than the usual one of quantum field theory on a background, and is based on…
We show that heavy primordial black holes may originate from much lighter ones if the latter are strongly clustered at the time of their formation. While this population is subject to the usual constraints from late-time universe…
Close encounters and physical collisions between stars in young dense clusters can result in new channels for stellar evolution, and may lead to the formation of very massive stars and black holes via runaway merging. We present some…
We use the formalisms of Holographic Space-time (HST) and Matrix Theory[11] to investigate the claim of [1] that old black holes contain a firewall, i.e. an in-falling detector encounters highly excited states at a time much shorter than…