Cars (whether powered by electricity, gasoline, or whatever) push against the road, and the amount of force (and thus energy) required as speed relative to the road increases.
But in space, we don't have roads. Rockets push against their reaction mass.
What is a hypothetical drive with no reaction mass pushing on?
But in space, we don't have roads. Rockets push against their reaction mass.
What is a hypothetical drive with no reaction mass pushing on?