Anti-Gravity vehicles will have increased potential energy as that lift off. That energy has to come from somewhere or we have to find a way around the conservation of energy.
Someone needs to find that “somewhere”. I don’t think they have so far.
“Anti-Gravity vehicles will have increased potential energy as that lift off.”
That kind of depends on how gravity actually works, doesn’t it? I mean, you’re thinking of it more like a classical mechanical problem, but according to relativity your motion is just a geodesic line in spacetime and the apparent curve that we see in the real world is an effect of the spacetime geometry, not some traditional force transmitting energy to accelerate you.