A new study envisions firing laser beams that would curve around a black hole and come back with added energy to help propel a spacecraft to near the speed of light.
Instead, Kipping suggests that gravity might assist spaceships by increasing the energy of laser beams fired at the edges of black holes.
Using what he called a "halo drive" — named for the ring of light it would create around a black hole — Kipping found that even spaceships with the mass of Jupiter could achieve relativistic speeds.
For example, halo drives would effectively steal energy from such , increasing the rates at which pairs of black holes merge above what one would expect to see naturally, Kipping said.
Although there are an estimated 10 million pairs of black holes in the Milky Way, Kipping noted that few of those likely orbited at relativistic speeds for long, since they would merge rather quickly.