English

Magnetic Extraction of Spin Energy from a Black Hole

Astrophysics 2009-10-31 v1

Abstract

Numerous variations have been proposed on the original suggestion by Blandford and Znajek that magnetic fields could be used to extract rotational energy from black holes. A new categorization of these variations is proposed so that they may be considered in a systematic way. "Black hole spindown" is defined more precisely, distinguishing decrease in the spin parameter a/M from decreases in angular momentum a and rotational kinetic energy, M - M_i. Several key physical questions are raised: Can the "stretched horizon" of a black hole communicate with the outside world? Do accretion disks bring any net magnetic flux to the black holes at their centers? Is the magnetic field adjacent to a black hole force-free everywhere?

Keywords

Cite

@article{arxiv.astro-ph/0008372,
  title  = {Magnetic Extraction of Spin Energy from a Black Hole},
  author = {Julian H. Krolik},
  journal= {arXiv preprint arXiv:astro-ph/0008372},
  year   = {2009}
}

Comments

to appear in "Explosive Phenomena in Astrophysical Compact Objects, Proceedings of the 1st KIAS Astrophysics Workshop"