Ah the eternal quandary of Sci-Fi writers on getting from here to there, when here is our Solar System and there is a number of light years away.

Physics says we can’t pass the Universal Speed limit of 186+KMPS, or 300KKPS, depending on where you got yer larnin.

So, we get Hyperdrive, Warp Drive, Sub-Space and all the rest.

Me? I use “Quantum Drives” and sort of glaze over the actual physics. Let’s be honest, who knows what kind of FTL drive is possible, if possible at all. For Norm-Space applications, nothing like Anti-matter initiated Fusion to move your mass along........;8~P.

But for Slow-Ships, the amount of reaction mass is so enormous to achieve relativistic speed I find it hard to see how it is possible to achieve. Even Ion drives will need a planetary sized amount of fuel to get anywhere near enough speed to make a noticeable relativistic difference. And let us not forget the radiation hazard from stray molecules impacting the ship at those speeds. Not to mention the occasional Gamma bursts the RL is so fond of. So we have to tote along a good sized shield, or figure out how to generate a Mega-Henry magnetic field to deflect such unpleasant interstellar weather.