English

Fermat's principle in black-hole spacetimes

General Relativity and Quantum Cosmology 2021-01-27 v1 High Energy Astrophysical Phenomena High Energy Physics - Theory

Abstract

Black-hole spacetimes are known to possess closed light rings. We here present a remarkably compact theorem which reveals the physically intriguing fact that these unique null circular geodesics provide the {\it fastest} way, as measured by asymptotic observers, to circle around spinning Kerr black holes.

Keywords

Cite

@article{arxiv.2101.06909,
  title  = {Fermat's principle in black-hole spacetimes},
  author = {Shahar Hod},
  journal= {arXiv preprint arXiv:2101.06909},
  year   = {2021}
}

Comments

5 pages. This essay received an Honorable Mention in the 2018 Essay Competition of the Gravity Research Foundation