Disclosing connections between black holes and naked singularities: Horizon remnants, Killing throats and bottlenecks

Abstract

We study the properties of black holes and naked singularities by considering stationary observers and light surfaces in Kerr spacetimes. We reconsider the notion of Killing horizons from a special perspective by exploring the entire family of Kerr metrics. To this end, we introduce the concepts of extended plane, Killing throats and bottlenecks for weak (slowly spinning) naked singularities. Killing bottlenecks (or horizon remnants in analogy with the corresponding definition of throats in black holes) are restrictions of the Killing throats appearing in special classes of slowly spinning naked singularities. Killing bottlenecks appear in association with the concept of pre-horizon regime introduced in [1, 2]. In the extended plane of the Kerr spacetime, we introduce particular sets, metric bundles, of metric tensors which allow us to reinterpret the concept of horizon and to find connections between black holes and naked singularities throughout the horizons. To evaluate the effects of frame-dragging on the formation and structure of Killing bottlenecks and horizons in the extended plane, we consider also the Kerr-Newman and the Reissner-Norstrom spacetimes. We argue that these results might be significant for the comprehension of processes that lead to the formation and eventually destruction of Killing horizons.

33 pages, 32 multi-panels figures, 3 Tables

References in corpus (10)

• Test bodies and naked singularities: is the self-force the cosmic censor?
• Ergoregion instability of ultra-compact astrophysical objects
• Circular motion of neutral test particles in Reissner-Nordström spacetime
• Destroying extremal Kerr-Newman black holes with test particles
• Collisional Penrose process near the horizon of extreme Kerr black holes
• Spherical gravitational collapse in N-dimensions
• Efficiency of the Keplerian accretion in the Braneworld Kerr--Newman Spacetimes and mining instability of some naked singularity spacetimes
• Particle collisions and optical effects in the mining Kerr--Newman spacetimes
• Rigidly rotating ZAMO surfaces in the Kerr spacetime
• Unbound geodesics from the ergosphere and potential observability of debris from ultrahigh energy particle collisions

Cited by in corpus (9)

• General relativistic rotational energy extraction from black holes-accretion disk systems
• Constraining LQG Graph with Light Surfaces: Properties of BH Thermodynamics for Mini-Super-Space, Semi-Classical Polymeric BH
• Repulsive regions in Lemaître-Tolman-Bondi gravitational collapse
• Jet collision with accreting tori around SMBHs. GRHD and light surfaces constraints in aggregates of misaligned tori
• Repulsive gravity effects in horizon formation. Horizon remnants in naked singularities
• On the metric bundles of axially symmetric spacetimes
• Extracting information on black hole horizons
• Distinguishing Black Hole and Naked Singularity in MOG via Inertial Frame Dragging Effect
• On light surfaces in black hole thermodynamics