>>> Rockets are certainly capable of accelerating a mass to a significant fraction of the speed of light. Well, yes and no. The speed of a rocket is limited b

>>> Rockets are certainly capable of accelerating a mass to a significant fraction of the speed of light. Well, yes and no. The speed of a rocket is limited by the specific impulse of its engines. That means that hydrogen-oxygen rockets aren't going to go very fast. Ion thrusters will go a lot faster, but take a long time to get up to speed. If you want to go really fast you need something really exotic like antimatter, but the technical challenges are quite daunting. Theoretically you could use a flashlight, but the batteries would run out before you could get anywhere. The allure of a reactionless drive is that you aren't limited by the the rocket equation. You may still need a big energy source, but your speed isnt limited by how fast you can spit stuff out your backend. It's fun reading to look up things like specific impulse, the rocket equation, relativistic rockets, even project Orion. IANARS.