So I making a story where there is FTL travel, but it is never referenced as actually being FTL. What is a good explanation of this, while still cutting a 4-light-year trip to a few hours?

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    $\begingroup$ I don't get your question. If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck. $\endgroup$ – L.Dutch - Reinstate Monica Nov 8 '19 at 13:10
  • $\begingroup$ Is an infinite lightspeed is an answer to your question? In all other cases faster than light travel would be faster then light! $\endgroup$ – ksbes Nov 8 '19 at 13:14
  • $\begingroup$ Wormholes? gives you most of the benefits of FTL, with potentially fewer downsides. $\endgroup$ – Starfish Prime Nov 8 '19 at 13:20
  • $\begingroup$ Call it warping. $\endgroup$ – The Square-Cube Law Nov 8 '19 at 14:11
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    $\begingroup$ Heh heh. Call it a spore drive. memory-alpha.fandom.com/wiki/Spore_drive Or a bistromathics drive. hitchhikers.fandom.com/wiki/Bistromathics $\endgroup$ – puppetsock Nov 8 '19 at 14:46

No FTL? Just Increase the Speed of Light

Just make light faster. What used to be a few light years away is now just a few light hours. It's what they used in Futurama.

And sadly by our current theories, it's probably the most scientifically sound idea we know. There is a theory that light used to be faster which explains the uniform cosmic microwave background distribution. We just have no idea how or why this happened.

That being said, I probably wouldn't use this explanation outside of a comedy series.

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    $\begingroup$ From Star Trek TNG: Q: Simple. Change the gravitational constant of the universe. LAFORGE: What? Q: Change the gravitational constant of the universe, thereby altering the mass of the asteroid. LAFORGE: Redefine gravity? How am I supposed to do that? Q: You just do it. $\endgroup$ – SRM Nov 12 '19 at 13:27
  • $\begingroup$ This answer prompted me to ask a new, related question: worldbuilding.stackexchange.com/questions/160705/… $\endgroup$ – SRM Nov 12 '19 at 13:42

As the ship powered up, the captain spoke over the intercom to the passengers, “Folks, please make sure you’re buckled into those gravity couches. I know they’re uncomfortable, but these new engines burn hot. We will be at Alpha Centauri in four hours. Burn starts in 60 seconds from my mark. ... Mark!”

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    $\begingroup$ +1 There's something to be said for not explaining all the things. Especially as FTL is one of those things that is generally accepted in scifi. $\endgroup$ – Starfish Prime Nov 8 '19 at 13:38
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    $\begingroup$ agreed, often in sci fi they just call them "hyperdrives" and that's about all the explanation you get. $\endgroup$ – John Nov 8 '19 at 14:51
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    $\begingroup$ Exactly. No one talks about firing up the Pratt and Whitney Turbofan Jet engine with the optimal fuel/air mixture and watching the oil levels. The pilot just says we'll be there in 4 hours. When you live in an era of technology that would appear miraculous to centuries past, you just take it as a matter of fact, (or grumble when your miraculous technology doesn't work right) Humans get inured to things easily. $\endgroup$ – SurpriseDog Nov 8 '19 at 16:43

There are a few different 'types' of ftl-travel that run a spectrum from 'pretty scientific' to 'totally made up' (e.g. Star Trek 'warp' which inspired the very possible Alcubierre Drive to Dune's spiced-up psychic navigators).

Here are some of them:


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Generally seems to be some sort of upper/lower/side dimension to the 'regular' universe we live in where a small amount of movement in it translates to massive distances relative to the 'regular' universe (imagine shrinking a 500px image down to 50px, traveling your pixel-sized craft 40px then blowing it back up to 500 again) - this appears in franchises like Stargate SG-1/Atlantis, and the Warhammer 40,000 universe (which additionally populates this 'hyperspace' world with demons and monsters.) where hyperspace becomes this 'place' you can spend time travelling in, for potentially long periods of time (within Stargate, they would often spend weeks at a time stuck on ships with blue hyperspace-stuff zipping past the windows) - visually these transitions are usually shown as if the ship is breaking open some barrier and going into/coming out of it.


'Timespace Warping':

enter image description here

Basically the function of the aforementioned Alcubierre Drive - As per Einstein's description of time being a lot like an elastic fabric, you warp the fabric in a way that either a) allows you to 'surf' on a moving wave of spacetime, or b) pull spacetime in the location you wish to travel to towards you, which creates this skewed visual effect on ships entering/exiting this mode of travel, and often times when they exit there's no inertia whatsoever, because as far as the people in the 'warp bubble' are concerned they've been completely stationary until arriving at their destination.

'FTL Drives':

enter image description here

(probably not what you're after) but these generally are the laziest answer and explain themselves something along the lines of *"f**ck Einstein I'm trying to write a story here - it works because it just does"*. If you want to be slightly more technical than that, it essentially involves the idea that the lightspeed barrier in the universe is more like a hill than an absolute non-negotiable wall, where after you pump enough energy into climbing over it, you pass it and can go faster than light in the same way earth (and all planets) have an 'escape velocity' needed to overcome that pesky 'what goes up must come down' "law".

As to how you reference these, it seems like a purely memetic problem - that is to say, an issue of popular/functional language. You can go full Rick and Morty if you want and call everything 'bloopledoops' or 'grumpleflonks' and everyone more or less understands what you're on about based on context, because the people who don't know what hyperdrives are generally happen also to be people that don't even know the timespace universe has a speed-limit.


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