Many vehicles, particularly Airships, utilise what is known as antimass; an array of one or more containers with reservoirs of an ionised superfluid that is subjected to a set of powerful, rotating electromagnetic fields. The effect this has on the fluid's gravitons leads to a negative weight, that is proportional to the mass of the volume times the rate of rotation. This creates an upward lifting force far exceeding what is possible with gasses lighter than air, nor does it require constant lateral motion as in aerofoils.
The altitude of an airship is regulated by the speed of the motors rotating the electromagnetic Charge Rods, which act upon the superfluid. Antimass requires a fairly large amount of energy to be supplied in order to drive the charge rods and the field, which is typically supplied by the airship's Vapour Drive. Still, even without power the effect lingers for a while before dissipating, making antimass safer than Rotaries for uninterrupted use. Antimass is also much more powerful than the Repulsor, but slower to respond and less precise to control.
Cities use a different method of lift; both unpowered and stable, but cannot be varied; called Floatrock.
The technology of antimass was such a cornerstone of Gold Age life that is was one of the few wonders from that time to survive and even remain somewhat ubiquitous, at least in major nations.