Artificial gravity (Earth-5875)

Artificial gravity is a technique used by the Covenant and its remnants and the Ecumene, in order to generate gravity of varying levels in zero or low-gravity environment.

Covenant
Majority of the Covenant's ships and vehicles used mechanisms that enabled artificial gravity, not involving the rotation of hull sections and acceleration.

Studies by UNSC scientists believe is that the Covenant was able to develop an alternate form of directional gravity emitter that can generate beams of graviton, meaning they are able to generate gravity without mass. The study implies that it's vastly possible the Covenant was able to discover how to convert energy into graviton particles, and then direct them like light, which seems to be the base for the gravity lift. The production of these "antigravitons" would then create repulsive effects which are more than likely basis for the boosted gravity propulsion drive and repulsor engines.