User:Snow Rise/sandbox/Halo drive

the Halo Drive is a proposed theoretical method for accelerating a spacecraft or other physical body to relativistic speeds of up to a significant fraction of the speed of light by firing a stream of photons along the gravity well of a blackhole, such that it returns to near its point of origin (forming the eponymous light beam halo); if utilized in conjunction with a binary blackhole system, the gravitational assist would return each photon in a blue-shifted state, and thus provide energy in excess to that which was used to propel it outward. Similarly, a single blackhole with enough rotational energy could be used to likewise blue-shift such photons. With either method, the stream of photons could be used to generate constant acceleration of a craft or other body--even theoretically bodies up to the scale of astronomical objects--driving it to relativistic speeds approaching closer to that of the speed of light than most spacecraft, including most speculative spacecraft.

If viable, the halo drive would would provide several advantages over many traditional proposed methods of interstellar travel, most notably in that an vessel using the method would not have to store much onboard fuel; with most other proposed methods of longterm spaceflight, fuel accounts for the vast majority of a craft's mass ratio. Furthermore, because the mass-energy of a blackhole is so massive in relation to the likely achievable mass of any craft utilizing the halo drive methodology, such maneuvers could provide virtually inexhaustible resources for interstellar travel, and/or an almost functionally arbitrary mass for a spacecraft, allowing for robust impact shields to mitigate the the effects of collision with interstellar gas and dust; interstellar dust, gas, and debris are otherwise often regarded as major constraints on the speed of proposed interstellar craft, since even microscopic amounts of matter would impact a theoretical craft with substantial force if said craft was traveling at relativistic speeds. A ship employing a halo drive method of propulsion would also be able to achieve much faster acceleration and sustain constant acceleration for significantly longer periods than most other proposed models for interstellar spacecraft. However, a craft employing halo drive propulsion would still need either massive energy reserves in order to decelerate, if the function of the craft was to do more than flyby observations, and amount of fuel necessary to supply this energy is so substantial that it is probable that a halo drive vessel would need another black hole system at it's destination in order to decelerate, by firing a stream of photons in a similar fashion to the method with which it first borrowed energy from the originating system.