Redshift rocket

Designed by novelist Karl Schroeder, the redshift rocket is a variant on the Sanger antimatter rocket. One of the key difficulties of harnessing the energy from matter/antimatter collisions is that most of the energy released by them is in the X-ray and gamma ray spectrum. The redshift rocket proposes to use particle beams, such as those produced by ultrafast laser pulses. Both the matter and antimatter would be accelerated to near light speed away from the spacecraft before colliding in the reaction chamber. This would lead to the radiation that reaches the spacecraft being redshifted. If the speed of the particle beams is great enough, the radiation that hits the spacecraft will be of a frequency that can be reflected. Energy absorbed by the spacecraft could be used to help power the particle beams.

Open questions include whether the energy required to accelerate the particles to such speeds will exceed the energy released from the collision, and whether the particles can be accelerated fast enough to achieve the desired redshift level.