The Gravity Diffusion system, or G-Diffusion, is an experimental power system used in starfighters that reduces gravity forces on the pilot and provides a respectable power source for shields and propulsion. The G-Diffuser system was created by John Tanaka, from the Galactic Federation and F-Zero game. However, due to the temperamental nature of the G-Diffuser, these systems need to be carefully checked and maintained; while easy to fix in flight, they can consume a pilots' full attention, something that kills pilots in a dogfight.
Possible explanations in real science
The G-Diffuser system appears to be a system intended to reduce the effects of gravity/acceleration on the pilot of an Arwing. The effects of this system might be duplicated by future advances in Zero-point Energy (ZPE) technology. ZPE is the so-called "background energy" of space, created by tiny pairs of particles that spontaneously appear in space as a result of Heisenberg Uncertainty. These particle pairs are theorized to cause electromagnetic drag on accelerating objects, resulting in the phenomenon that we know as inertia. Harnessing the Zero-Point Energy could result in a nearly limitless power supply as well as certain theorized antigravity/inertialess effects, coincidentally duplicating the action of the G-diffuser system.