paper

Twisted light, a new tool for General Relativity and beyond

arXiv:2107.01599 · doi:10.1142/S0218271821420177

Abstract

We describe and present the first observational evidence that light propagating near a rotating black hole is twisted in phase and carries orbital angular momentum. The novel use of this physical observable as an additional tool for the previously known techniques of gravitational lensing allows us to directly measure, for the first time, the spin parameter of a black hole. With the additional information encoded in the orbital angular momentum, not only can we reveal the actual rotation of the compact object, but we can also use rotating black holes as probes to test General Relativity.

This essay received an Honorable Mention in the 2021 Essay Competition of the Gravity Research Foundation. v2: published version

References in corpus (5)

Twisted light, a new tool for General Relativity and beyond · wovepaper