David Kipping Explains the Black-Hole Halo Drive

HN readers point to it as a clear explanation of a theoretical fuel-free propulsion concept from a channel they respect.

Astrophysicist David Kipping presents the halo drive, a proposed way to propel a starship to a good fraction of light speed by gaining energy from a black hole. The video is based on his peer-reviewed paper and explains why energy is the main obstacle to interstellar flight.