相关论文: Irreducible mass and energetics of an electromagne…
The concept of the irreducible mass ($M_{\rm irr}$) has led to the mass-energy ($M$) formula of a Kerr black hole (BH), in turn leading to its surface area $S=16\pi M_{\rm irr}^2$. This also allowed the coeval identification of the…
We investigate the energy distribution of a black hole in various spacetimes as reckoned by a distant observer using the quasi-local energy approach. In each case the horizon mass of a black hole: neutral, charged or rotating, is found to…
We analyze the extraction of the rotational energy of a Kerr black hole (BH) endowed with a test charge and surrounded by an external test magnetic field and ionized low-density matter. For a magnetic field parallel to the BH spin,…
The energy extraction from a Einstein-Born-Infeld (EBI) black hole is addressed determining the extension of the ergosphere as well as the extractable energy using the irreducible mass concept. These results are compared with the…
Relying on the Penrose process mechanism, we study the possibility of energy extraction from a binary system composed of two extreme electrostatic black holes (BHs) oppositely charged, separated by a strut described by Bonnor's metric (BM).…
It has been thought for decades that rotating black holes (BHs) power the energetic gamma-ray bursts (GRBs) and active galactic nuclei (AGNs), but the mechanism that extracts the BH energy has remained elusive. We here show that the…
The mass--energy formula of black holes implies that up to 50% of the energy can be extracted from a static black hole. Such a result is reexamined using the recently established analytic formulas for the collapse of a shell and expression…
This article presents an analysis of regular rotating black hole solutions within the framework of Teleparallel Equivalent to General Relativity (TEGR). The study evaluates the total energy and derives an analytical expression for the…
We investigate the extraction of rotational energy from rotating Einstein-Born-Infeld (EBI) black holes, where nonlinear electrodynamics introduces a radius-dependent effective charge modifying the spacetime geometry. Focusing on neutral…
We evaluate the \emph{surface energy~(${\cal E}_{s}^{\pm}$), rotational energy~(${\cal E}_{r}^{\pm}$) and electromagnetic energy~(${\cal E}_{em}^{\pm}$)} for a \emph{Kerr-Sen black hole~(BH)} having the event horizon~(${\cal H}^{+}$) and…
We explore the extraction of energy from a rotating black hole spacetime modified by a quantum correction parameter \( \alpha \). Focusing on particle splitting within the ergoregion, we analyze the Penrose process and compute the…
We analyze the consequences of the recently found generalization of the Christodoulou-Ruffini black hole mass decomposition for Einstein-Born-Infeld black holes [characterized by the parameters $(Q,M,b)$, where $M = M(M_{irr},Q,b)$, $b$…
Spinning black holes store rotational energy that can be extracted. When a black hole is immersed in an externally supplied magnetic field, reconnection of magnetic field lines within the ergosphere can generate negative energy (relative to…
We set to weigh the black holes at their event horizons in various spacetimes and obtain masses which are substantially higher than their asymptotic values. In each case, the horizon mass of a Schwarzschild, Reissner-Nordstr{\"o}m, or Kerr…
We investigate mechanisms of energy extraction from a rotating black hole in terms of negative energy-at-infinity. In addition to the Penrose process through particle fission, the Blandford-Znajek mechanism by magnetic tension, and the…
With the Komar mass formula we calculate the electromagnetic energy for a charged Kerr black hole in a uniform magnetic field. We find that the total electromagnetic energy takes the minimum when the Kerr black hole possesses a non-zero net…
The mass of a Kerr black hole can be separated into irreducible and rotational components -the former is a lower limit to the energy that cannot be possibly extracted from the event horizon and is related to its area. Here we compute the…
The rotational properties of astrophysical black holes are fundamental quantities that characterization the black holes. A new method to empirically determine the spin mass-energy characteristics of astrophysical black holes is presented…
It is argued that the nonintegrably singular energy density of the electron's electromagnetic field (in both the classical point-charge model and quantum electrodynamics) must entail very strong self-gravitational effects, which, via black…
A new scenario for extracting energy from a Kerr black hole is proposed. With magnetic field lines connecting plasma particles inside the ergosphere with remote loads, the frame dragging twists the field lines so that energy and angular…