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A Measurement of the Electromagnetic Luminosity of a Kerr Black Hole

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Paper breakdownThe authors' claims, conditions and measurements, as JSON Signed receiptProof this review has not been altered
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Jonathan C. McKinney (1, 2), Charles F. Gammie (1, 2, 3) ((1) UIUC Center for Theoretical Astrophysics, (2) UIUC Department of Physics, (3) UIUC Department of Astronomy)

Astrophysics · Submitted 26 Apr 2004

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim We find that (1) low density polar regions of the numerical models agree well with the Blandford-Znajek model; (2) many of our models have an outward Poynting flux on the horizon in the Kerr-Schild frame; (3) none of our models have a net outward energy flux on the horizon; and (4) one of our models, in which the initial disk has net magnetic flux, shows a net outward angular momentum flux on the horizon.

how it is stated · asserted 1.00 read the record →

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arXiv IDastro-ph/0404512 (version 1)
Pith ID4DMD2N56, Pith's permanent record of this paper and its review
Citation2, 2), (2) UIUC Department of Physics, 3) ((1) UIUC Center for Theoretical Astrophysics, (3) UIUC Department of Astronomy), Charles F. Gammie (1, Jonathan C. McKinney (1. "A Measurement of the Electromagnetic Luminosity of a Kerr Black Hole." arXiv:astro-ph/0404512 (2004). https://pith.science/paper/4DMD2N56
Claim paper

The compiled record

The paper's own sentences, arranged. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Open the compiled record

Compiled by classifier-1.13.0 via TypeSafe API, question bank abstract-p1-20260923, 2026-09-23: 1 request, 6,407 input tokens.

What the abstract itself states, as probabilities: claims first 0.03 · states limitation 0.90 · human participants 0.01 · controlled comparison 0.18 · randomized assignment 0.01 · states quantitative result 0.50 · compares with prior results 0.97 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; .

Some active galactic nuclei, microquasars, and gamma ray bursts may be powered by the electromagnetic braking of a rapidly rotating black hole. We investigate this possibility via axisymmetric numerical simulations of a black hole surrounded by a magnetized plasma. The plasma is described by the equations of general relativistic magnetohydrodynamics, and the effects of radiation are neglected. The evolution is followed for $2000 G M/c^3$, and the computational domain extends from inside the event horizon to typically $40 G M/c^2$. We compare our results to two analytic steady state models, including the force-free magnetosphere of Blandford & Znajek. Along the way we present a self-contained rederivation of the Blandford-Znajek model in Kerr-Schild (horizon penetrating) coordinates. We find that (1) low density polar regions of the numerical models agree well with the Blandford-Znajek model; (2) many of our models have an outward Poynting flux on the horizon in the Kerr-Schild frame; (3) none of our models have a net outward energy flux on the horizon; and (4) one of our models, in which the initial disk has net magnetic flux, shows a net outward angular momentum flux on the horizon. We conclude with a discussion of the limitations of our model, astrophysical implications, and problems to be addressed by future numerical experiments.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#sentencerolethe authors' own workstates the main conclusionstrength
s0 Some active galactic nuclei, microquasars, and gamma ray bursts may be powered by the electromagnetic braking of a rapidly rotating black hole. background 1.00 0.04 0.04 hedged possibility 1.00
s1 We investigate this possibility via axisymmetric numerical simulations of a black hole surrounded by a magnetized plasma. method 0.63 0.93 0.02 asserted 0.77
s2 The plasma is described by the equations of general relativistic magnetohydrodynamics, and the effects of radiation are neglected. method 0.96 0.51 0.02 asserted 0.98
s3 The evolution is followed for $2000 G M/c^3$, and the computational domain extends from inside the event horizon to typically $40 G M/c^2$. method 1.00 0.91 0.02 asserted 0.99
s4 We compare our results to two analytic steady state models, including the force-free magnetosphere of Blandford & Znajek. method 0.92 0.82 0.02 asserted 0.91
s5 Along the way we present a self-contained rederivation of the Blandford-Znajek model in Kerr-Schild (horizon penetrating) coordinates. contribution 0.81 0.95 0.02 asserted 0.99
s6 We find that (1) low density polar regions of the numerical models agree well with the Blandford-Znajek model; (2) many of our models have an outward Poynting flux on the horizon in the Kerr-Schild frame; (3) none of our models have a net outward energy flux on the horizon; and (4) one of our models, in which the initial disk has net magnetic flux, shows a net outward angular momentum flux on the horizon. result 1.00 0.97 0.83 asserted 1.00
s7 We conclude with a discussion of the limitations of our model, astrophysical implications, and problems to be addressed by future numerical experiments. future work 0.83 0.41 0.06 unclear 0.90

What kind of paper the classifier reports this is: simulation study 1.00 · evidence from simulation or computation 1.00.

What was examined, and what was not

sources read
  • arXiv listing abstract v1
not examined
  • full text
  • figures and tables
  • references and citing sentences
  • relations to other papers
levels run
  • P abstract
not run
  • S sections
  • T body sentences
  • C citations
  • R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

The paper
Original abstract

Some active galactic nuclei, microquasars, and gamma ray bursts may be powered by the electromagnetic braking of a rapidly rotating black hole. We investigate this possibility via axisymmetric numerical simulations of a black hole surrounded by a magnetized plasma. The plasma is described by the equations of general relativistic magnetohydrodynamics, and the effects of radiation are neglected. The evolution is followed for $2000 G M/c^3$, and the computational domain extends from inside the event horizon to typically $40 G M/c^2$. We compare our results to two analytic steady state models, including the force-free magnetosphere of Blandford & Znajek. Along the way we present a self-contained rederivation of the Blandford-Znajek model in Kerr-Schild (horizon penetrating) coordinates. We find that (1) low density polar regions of the numerical models agree well with the Blandford-Znajek model; (2) many of our models have an outward Poynting flux on the horizon in the Kerr-Schild frame; (3) none of our models have a net outward energy flux on the horizon; and (4) one of our models, in which the initial disk has net magnetic flux, shows a net outward angular momentum flux on the horizon. We conclude with a discussion of the limitations of our model, astrophysical implications, and problems to be addressed by future numerical experiments.

Human review

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References
How later papers used it

154 later papers cite it

Evidence: substantial. 146 of the citing papers share no author with it, and 54 of those carry a confident label from Pith's citation classifier.

Pith read 18 of the 252 citing sentences, choosing only those whose citation markers point at this paper alone, and wrote the paraphrases from them. The summary, the counts, the evidence level, the links and the quotes come from code; the summary counts the papers listed below. A later paper is listed under a label when Pith's citation classifier gives one of its sentences that label at probability 0.8 or more (0.95 for support), Pith's reading finds that the citing paper itself did it, and a second check confirms the paraphrase against the sentence. This section lists uses only. It does not list criticism or disagreement, so their absence here says nothing about how the paper has been received. Papers that share an author with this one are listed apart, under "By the same authors". A quote is the citing authors' own sentence, shown when their paper's licence is CC BY, CC BY-SA or CC0. JSON

Uses its method or tool 5 of 39 papers with this label
Compares with it 1 of 6 papers with this label
How the literature uses it

60 arXiv papers cite this in 102 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 59 sentences without a confident label

Uses its method or tool 12 papers
Uses its data or values 2 papers
Compares with it 2 papers
Cites it as support 4 papers
Cites it as background 15 papers

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