[estimator7292]

I don't like antimatter because it's the most volatile fuel possible. If power is ever interrupted for any reason for any amount of time, the entire mass explodes.

A slightly less insane fuel source is a micro black hole. Drag a tiny black hole behind your ship and drip-feed it any kind of mass you come across. You still get >90% mass-energy efficiency which is far beyond anything else we know of.

Besides, one of the big problems with antimatter is that it's a battery, not a fuel source. We must first collect the unimaginable amount of energy and then process it into antimatter one particle at a time. If you build a ton of factories around a star you can get meaningful production. But a black hole drive can suck up interstellar gas or any asteroids you come across. Matter is easy to get. Don't ask where the micro black hole comes from.

[andrewflnr]

Black holes have similar problems to antimatter. A micro black hole is pretty close to an ongoing antimatter explosion in terms of effects on its surroundings. If any part of your shielding fails, it irradiates you or melts you. Their radiation increases as they get smaller, and if not fed they're always getting smaller, until they "explode" (yes, but even more so) and disappear. So you still have the problem that if you don't maintain it just right, it will annihilate your ship. So, "less insane" is dubious IMO. (Still my favorite starship idea, though.)

[ant6n]

How heavy is the micro black hole? How do you “drag” it?