Believe so, but the major limiting factor is the amount of mass that you can carry to eject out the back of your ship. The Expanse series is predicated on the

Believe so, but the major limiting factor is the amount of mass that you can carry to eject out the back of your ship. The Expanse series is predicated on the development of a reactionless drive that converts energy directly into thrust without expenditure of mass. If such a technology existed, you could get going pretty fast just motoring along at a constant 1-g acceleration, and have "gravity" too.