Electron-Positron Jets from a Critically Magnetized Black Hole

TL;DR

This paper investigates how a rotating black hole in a near-critical magnetic field can produce copious electron-positron pairs, revealing potential high-energy astrophysical phenomena.

Contribution

It demonstrates that a maximally rotating black hole in a magnetic field close to the quantum critical value can generate intense electron-positron pair production.

Findings

Black holes in near-critical magnetic fields are unstable.

Such black holes can produce electron-positron pairs with luminosities up to 3 x 10^{52} erg/s.

The process could explain high-energy astrophysical emissions.

Abstract

The curved spacetime surrounding a rotating black hole dramatically alters the structure of nearby electromagnetic fields. The Wald field which is an asymptotically uniform magnetic field aligned with the angular momentum of the hole provides a convenient starting point to analyze the effects of radiative corrections on electrodynamics in curved spacetime. Since the curvature of the spacetime is small on the scale of the electron's Compton wavelength, the tools of quantum field theory in flat spacetime are reliable and show that a rotating black hole immersed in a magnetic field approaching the quantum critical value of $B_k=m^2 c^3/(e\hbar) \approx 4.4 \times 10^{13}$~G $\approx 1.3\times10^{-11}$ cm$^{-1}$ is unstable. Specifically, a maximally rotating three-solar-mass black hole immersed in a magnetic field of $2.3 \times 10^{12}$~G would be a copious producer of electron-positron pairs with a luminosity of $3 \times 10^{52}$ erg s$^{-1}$.