Energy extraction from extremal electrovacuum black holes through collisional Penrose process
Presenting author: Filip Hejda
The so-called Baņados, Silk, West (BSW) effect of high-energy, near-horizon particle collisions has enjoyed a lot of attention in the literature. Yet up until recently, it suffered from serious drawbacks regarding the possibility of energy extraction through such collisions. Namely, in the original version involving maximally spinning black holes, the extracted energy turned out to be subject to unconditional upper bounds. Although such bounds were not found in the purely electrostatic variant of the process, this version is also astrophysically unfeasible, since it requires maximally charged black hole. Our work is focused on surpassing those problems by generalising the process to extremal black holes with arbitrarily small value of charge, which serve as a simplified model of fast-spinning astrophysical black holes with tiny charge accreted due to Wald's mechanism. Building up on our previous results [Phys. Rev. D 95, 084055 (2017); Phys. Rev. D 100, 064041 (2019)], the present talk focuses on new possibilities that arise for energy extraction via collisions of charged particles in the equatorial plane.
Oral presentation: yes. Poster: no.