[Spaceships] Your preferences regarding plausible/playable Reactionless Drives

[malloyd]

Originally Posted by Fred Brackin

I can only say that I have never seen any consequences to the game from either butchering or complying with relativity.

Neither have I. The negative consequences of reactionless drives are the missile with ridiculous kinetic energy (which happens with any fast spacecraft drive that cares about physics at all), and the cosmic power plant (from their violation of conservation of energy, which always happens in the Newtonian case and happens when they are better than photon drives in the relativistic one).

Ditching relativity, at least if you do it with a preferred frame, isn't likely to have any effect on the game. OK, technically magnetism goes away, light vanishes as electromagnetism becomes impossible, nuclear reactions stop working and the sun goes out for lack of an energy source, and atoms fall apart when the binding energy disappears, but you can simply declare Maxwell's equations and mass to energy equivalence fundamental laws rather than logical consequences of relativity.

A quantum mechanical handwave is really no better. It solves neither of those actual problems and causes just as much damage to the rest of physics - modern physics is pretty highly interconnected. And if you are concerned about your players exploiting the loopholes (though you probably shouldn't be, if they aren't willing to ignore them by GM fiat they clearly don't want to play in a campaign with good space drives), it is likely to have more easily abused ones, since it isn't likely to require difficult to engineer tremendous speeds, distances or energies to produce them.