Hopefully the title sums it up well, but I'm looking for potential faster than light travel (hoping for real or pseudo-real science here, as much as possible) that doesn't involve a warp drive, which is literally the only theory I know of that defines it as impossible without breaking general relativity - but I'm writing about a civilization so far into the future that calling someone Einstein is an insult, referencing how simple and misguided his theories were/led civilization down the wrong path for centuries due to no one thinking outside his box (I don't actually believe this, I think his work will eventually be "disproved" in some manner, but absolutely fundamental for humanity to get that far in the first place - doesn't mean that can't be lost on a civilization over a 1000 years later with insanely advanced science).

For background, this story begins in 1042, the switch to the new calendar isn't detailed in depth, but occurred around the years 2640-2680 AD. This is a unified, single government Earth with all peoples living in a relative Utopia(or at least believing so, kind of irrelevant to the story, actually). The formation of this new world order is loosely based on western ideologies but focuses on a "healthy" (please don't make me define that!) mix of socialism and capitalism in a true democratic society (technology/AI handles most logistics and enforcement, global votes are held as often as 10% of the population pushes forward any proposal, anyone can propose literally anything, yadda yadda). They have near lightspeed travel after effectively adapting photon cannons developed in war to act as engines in space. They have a firm grasp on what we now describe as anti-matter, describing it instead as "hidden energy", and are able to utilize it in our reality. Our main character was appointed as Director of the Department of Energy in 1026, and has used a bulk of the funding and manpower to achieve faster than light travel, not by a warp drive, but by literally breaking the light barrier (think breaking the sound barrier), and simultaneously clearing the space in front of the ship of all matter by absorbing it and converting it to fuel nearly instantaneously. This does imply an absolute necessity to plot courses carefully, and be extremely careful of traveling through planets and stars, not for the ships safety, but for the gravitational implications of eating a ship sized hole (more so in planets) through something as it travels through. Think a bullet through an apple. Like a wormhole type of travel but literally just ripping through space, matter, and time instead of going around it in another dimension, and the 'wormhole' closes up more or less instantaneously after the ship travels through. However I'm entirely unsatisfied with the "plausible" explanations I've come up with for how this travel actually works. I realize that's because real, modern science doesn't support it as plausible in the first place. Any ideas?

I just want it to be less "hand-wavey"

EDIT: I say faster than light travel without utilizing a warp drive where the term "warp drive" is defined as the ability to achieve faster than light travel by warping space-time around the ship, rather than the ship itself traveling through space-time. I'm very specifically looking for faster than light travel through space-time. "Breaking the light barrier" is a necessary part of the plot.

EDIT 2: To add a couple more details here, this is a brand new development in this society, the main character is presenting his proofs, the opening is an interview with a reporter to describe the new advancements. This is only described in theory until near the end of the story, where they've built out and do the first practical test. To give away the ending, this test is world ending due a miscalculation and hubris preventing it's discovery until too late. They can't actually travel faster than light as they propose. I don't actually need it to be science based and safe - just seem plausible and with a slight equation tweak so it appears safe, but that mistake causes quite a catastrophe when put into practice. The protagonist actually describes in detail his disdain for previous directives disallowing study into warp drives by the department of energy, due to past catastrophes (warp drives at first appeared successful, but no one ever came back, if they did reach a destination), but finds it irrelevant now as he and his department have achieved it without a warp drive, or at least believe they have.

  • $\begingroup$ Comments are not for extended discussion; this conversation has been moved to chat. $\endgroup$
    – L.Dutch
    Aug 11, 2020 at 12:31

18 Answers 18


Let's set the technobabble aside

You can name your drive/engine/motor/causal-difference-generator anything you want. It's important (don't ignore it), because what you're really going to do is choose one of the options below (or one of those suggested by my compatriots), pretty much all of which have been used in scifi before, and then apply your unique spin on it. So, no technobabble, that's your job.

So, what are your options?

Let's completely ignore what we believe are the limitations of physics. Let me be 100% honest about this — those limitations are, at best, only what we understand today. It's a bit surprising that anyone would believe that what we know today is the end-all of knowledge, but we humans do it all the time. So, the limitations are interesting...

...but we're going to completely ignore them.

Raw Speed You've invented "inertial dampers" (the magical solution of ignoring acceleration that would turn normal people into strawberry jam before proving that under the right conditions strawberry jam is a perfectly sound fuel for nuclear fission), and so you can accelerate until the cows come home! In this situation, you're FTL because you can with raw, unadulterated horse power!

Curved Space You've finally resolved those pesky lawsuits with Paramount® and you can finally pull the trigger on Warp Drive®! Your pretty new engine (named the "William Shatner Drive®" as one of the bargaining concessions to settle the lawsuits) bends space like a fully-paid-for Photoshop effect. This allows you to travel a much shorter distance, making it only appear that you're FTL. Your actually moving just a hair faster than Apollo 15. (Huh? What do you mean Adobe's on the phone? Whatdaya mean we forgot their trademark symbol? A lawsuit! Dang nabit...)

Pinched Space If curved space is a bit slow for you, there's always the possibility of pinched space. Some people like to refer to this as "wormholes," but they're the unwashed barbarians of the throw-physics-out-the-window community. Think about using your two hands to pinch two locations on your favorite bed sheet, then draw those pinched portions together! Maybe travel is instantaneous (you know, infinitely FTL) or maybe it takes a moment of time (you know, like chasing the DS9 Prophets in their Celestial Temple... Paramount's on the phone again? Tell'm to suck an egg!) Anyway, an argument could be made that this is the same thing as curved space, but it's not, it's the punch-a-hole-through-it solution. (I loved an episode from Stargate SG-1 when a traveler tries to explain to Samantha Carter how they move through space, he's basically the source of my pinch-the-sheets metaphor. "Oh!" Carter exclaims, "Like an Einstein–Rosen bridge!" "No," the traveler says sadly, shaking his head, "it's not like that." Do you see what I mean by "technobabble?")

Alternate Space Also known as inter-dimensional travel or moving through space, between space, or through another space — whichever path is shorter, right? One of my favorite authors is Jack Vance and his Intersplit drive. It was his version of "hyperspace," such that a crack was opened in "real space" and his ship could slip through it. Heaven only knows what the rules of those other "spaces" could be! And, obviously, there are an infinite number of them.

Have I missed anything? Pure horsepower, jump the gap, tunnel through a shortcut, leave space entirely... diving headlong into a black hole would be tunneling through a shortcut... Personally, I think Star Trek is more pure horsepower where the remake of Battlestar Galactica is more like jumping the gap. Could be wrong about that... How about this?

Gravitic Shear What if your engine creates a "potential difference" with gravity similar to what we do with electricity (aka, "voltage")? Once the difference is established (a "shear"), you ride it like you would a wave with a surfboard. But this might be a hybrid of horsepower and curved space.

Infinite Improbability To make a point, one of the most creative solutions to this problem was Douglas Adams' Infinite Improbability Drive. The idea was so ingenious that most of us have been banging our heads against walls trying to be as creative ever since. The engine magically decreases probability to zero until the ship is literally everywhere in the universe at the same time. The target location is selected, and probability increased (think, "I'm probably here..." Adams was a genius author) to unity. (Or did I get that backwards... anyway...). This was a clever, wholly unscientific, fundamentally irrational, and absolutely genius way of getting from point A to point B in the least amount of time (but not always with the least amount of trouble).

It's All a Simulation @ReinstateMonica reminds us that the universe could be a simulation! How would we know, right? Well... you're pilot is The One and happens to know how to hack the code! Instantly the ship arrives at its destination!

And I can't think of any more. But that brings me to my last point.

Maybe you don't need to be this specific

Yes, SciFi has described these things in myriads of ways — but with rare exception, the specifics of exactly what is happening are ignored. I recommend that behavior. If you tell a good story, people will fill in the details with their own imagination. If you fill your book with details but tell a substandard story, most people will choke on what you're trying to explain. I recommend that you be wary of trying to crowbar too much science into fiction (just enough to relate, not enough to distract) because in the end, you're stuck facing the limitations I suggested ignoring in the beginning. It's a form of spinning your tires. So, dream up some impressive technobabble to briefly explain that your ship can do something that, today, we believe is simply impossible. Then let that ship fly.

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    $\begingroup$ Comments are not for extended discussion; this conversation has been moved to chat. $\endgroup$
    – L.Dutch
    Aug 11, 2020 at 12:35

Imagine that all of our existing physics equations are incomplete. In each and every case, the formulae that our smartest minds have discovered actually contain one or more as-of-yet undiscovered components which must be multiplied against one or both sides of the equation to accurately describe reality. Now imagine that the reason that our smartest minds haven't noticed these omissions is that our entire solar system resides in a part of the universe where those components all hold a constant value of exactly one. So, for the portion of the universe which we can directly observe, those undiscovered components act as "multiply-by-one" harmless players in the formulae which we create and validate. We can never discover these components through scientific exploration because within our scope, those components never fluctuate and in their constancy, they become invisible to us.

Now imagine that one or more of these hidden components are not constant under all conditions within our part of the universe. They are constant at exactly one almost everywhere, but under an extremely rare and specific set of conditions (gravity, heat, radiance, sound, electrical charge and maybe even thought or belief), the hidden formula components can be changed to values which allow FTL to occur.

The process of discovering how to travel FTL would then be simple yet dangerous. The trick would be to find that rare set of physical conditions which allow for FTL before you accidentally change one of the other hidden components which might disallow life or matter or time.

Best of luck in your endeavors! ...for all of our sake!

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    $\begingroup$ This is exactly along the line I was looking for. Just getting another step further, but along the path I was going. I won't accept an answer for at least 24 hours, maybe 48, as is common practice for the global community - but thank you either way! Whether or not this is the final thing I go with, it'll be included. $\endgroup$
    – TCooper
    Aug 7, 2020 at 0:09
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    $\begingroup$ Or instead of multiply by one, add some constant multiplied by a factor that (until some future discovery) is so small as to be effectively zero. This is not too far off from how Einstein’s equations “improved” Newton’s. $\endgroup$
    – StephenS
    Aug 7, 2020 at 5:25
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    $\begingroup$ Considering we are having e.g. GR being verified by our observations of objects billions of light years away, there would have to be some very special and Solar-centric equations, at which point you can just say "everything outside the Solar system is just a hologram fed to us by god-like aliens". $\endgroup$
    – Alice
    Aug 7, 2020 at 7:01
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    $\begingroup$ Ironically our existing physics equations are incomplete. That is why they are always continuing the research. Satellites are in orbit with technology build with incorrect theories. The hidden properties is very much what we're now looking for. See dark matter. Theorised because we see something we don't understand. We search for the hidden parameters of the universe to find out how it works and how it can benefit mankind. $\endgroup$
    – Trioxidane
    Aug 7, 2020 at 8:43
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    $\begingroup$ "So, for the portion of the universe which we can directly observe..." Change "universe" to "galaxy," and you have the setting for Vernor Vinge's Zones of Thought series. $\endgroup$
    – Michael
    Aug 7, 2020 at 14:54

The X Drive.

How does an X drive work, it doesn't matter, you are not writing a technical manual. For a story all you need is the rules it works by and a name. Most technology is black box technology to the people that use it, they only understand the rules. Use the name of the inventor that leaves no hint as to how it works. FTL drives are pure fiction, so just like a magic system all you need is steadfast rules about how they work and they will still feel consistent and scientific. Imagine trying to explain to a caveman how a radioisotope thermoelectric generator works, they don't know what atoms, nuclear or electricity are so no explanation will make sense. Explaining a FTL drive to us would have the same problem it has to utilize principles or forces we haven't discovered, so any explanation is indistinguishable from hand-waving.

If you want examples try wikipedia, https://en.wikipedia.org/wiki/Category:Faster-than-light_travel_in_fiction, this is not the place for that.

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    $\begingroup$ Similar points to the current top answer, thank you for posting. I'm glad I have the input of so many people on this, but also realize (thanks to you great folks) I over-thinking it $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:52

For centuries Special Relativity reigned supreme. Discovery after discovery supported Einstein's theory. The equations held up. All the energy in the Universe is required to accelerate matter to the speed of light, much less past it.

Nobody even bothered to try breaking the light barrier. They just accepted the math as law.

Around the turn of the new, new millennium, an imaginative doctoral candidate in physics was staring listlessly at the ocean. A storm was blowing in. The tide was rising, and the waves toppled over themselves. A moment of inspiration washed over her. "That's it!" she thought. "The light wave just roles over itself!"

So convinced we were. The faster you go light shifts towards the blue end of the spectrum, squashing the energy wave together. At c the equation says you can't go any faster. The energy required is infinite. "Except, what if the wave inverts itself, and begins to red-shift as speed continues to increase and begins to stretch back out?" she pondered.

She spent the next 7 years developing the math to prove it was feasible. The numbers added up. You can break the light barrier! The challenge is getting the energy.

Not long after her trip to the ocean, another daydreaming physicist came up with the hair brained idea of a mass-energy transference skin. A skin of material absorbs matter and converts it to energy. All you need to do is run into it. Math ensues, papers are published and colleagues laugh at him.

The Director of the Department of Energy wasn't laughing. The director was intrigued. He had also heard a lecture from our seaside dreamer about breaking the light barrier. Of course she gets laughed out of the auditorium, but the director wasn't so sure her ideas were crazy.

He connects the two physicists, and realizes the of skin of the ship could absorb matter and convert it to the energy required to topple over that light wave. Just ram your ship into enough matter, and boom. Speed boost without warping spacetime.

So sure they were of the math, that you can break the light barrier. Nobody ever imagined what that would do. The wave just topples over itself, right?


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    $\begingroup$ Aside from the fact that special relativity was superseded over a century ago by general relativity, and the misunderstanding of why the limit is there in the first place...how about not slandering every scientist and engineer who's dealt with relativity since Einstein? The claim that everybody "just accepted the math" is completely counter how science is practiced. Relativity has been systematically tested from the start, with researchers concocting new tests and new measurement techniques all the time. $\endgroup$ Aug 7, 2020 at 17:41
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    $\begingroup$ @ChristopherJamesHuff I assume he was writing that to coincide with my details of calling someone Einstein an insult because it's so far in the future and general relatively seems mind numbingly simple to the average high school student in this society. I don't think Greg or myself has any misgivings towards any scientist, A.E. or otherwise - just trying to help write a fiction piece. I had to remove the science based tags anyway, so I can work out why the energy isn't actually infinite as it moves past light speed $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:50
  • $\begingroup$ @ChristopherJamesHuff: Yeah, please don't think I'm trying to offend scientists in any way. I was just trying to make connections between the original question and my idea. That's all. $\endgroup$ Aug 7, 2020 at 20:05
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    $\begingroup$ That's fair. It's just that there is this persistent belief among some of the general public that it's really possible to make groundbreaking discoveries by ignoring well-established theories, but when people get caught up in that mindset, it winds up being annoying at best to dangerous at worst. So scientists can get more than a little irritated whenever someone talks (or, I guess, writes) like that. $\endgroup$
    – David Z
    Aug 8, 2020 at 0:17
  • $\begingroup$ This scenario makes no sense to anyone who understands how science is done. Many physicists spend time trying to come up with alternative mathematical models that explain all the experiments done so far, but would give different results when pushed to extremes. If this "imaginative doctoral student" really could back up her theory with rigorous math, she would not be laughed at by other scientists. And you'd also need some reason besides "genius" that no one was able to work this out before -- e.g., a breakthrough in mathematics or computational power. $\endgroup$ Aug 8, 2020 at 12:26

Your problem is you are too close to what you are trying to set up. Basically you are trying to build a world where a form of faster-than-light (FTL) travel is being developed that end catastrophically. That's simple enough to deal with.

You also want to avoid using something like the Alcubierre warp-drive. A concept that is modestly plausible as an FTL drive, but not without its perceived problems. That's easily done. Say, that in future it was comprehensively found to be impossible.

Your near-lightspeed travel is essentially an interstellar ramjet that converts any matter it encounters into kinetic energy. The lightspeed barrier cannot be broken like the sound barrier. Not as we currently understand the science. Future science may find a work-around, but don't bet on it.

FTL travel might be achieved by a sort of continuously generated wormhole that keeps shifting a spacecraft across distances faster-than-lightspeed. This is pure hand-waving. Here the phrase "might be achieved" only means that it sounds hand-waving plausible. This is all that is needed for fiction. So could shifting into higher dimension space where the distances between astronomical objects is vastly shorter than in normal 4-space. (4-space is the term top describe our normal spacetime.) There is a wide variety of fictionally plausible notions used by science-fiction to "justify" FTL travel. Often is best to simply say it works without explaining how or why.

There is a simple idea that can explain an FTL drive goes catastrophically wrong. It comes from the real world and is bound to apply in fictional situations. basically things that work well on the laboratory scale often fail when they're scaled up to real-world industrial scales.

Assume an FTL drive is developed. It works absolutely well for small test vehicles. But it has an hitherto undiscovered flaw. Something that hasn't merged from the mathematics describing the science behind the FTL drive.

For example, there could be a wormhole that grows exponentially with the size of the FTL drive that causes energy to leak from a higher dimensional space. With small test vehicles this is negligible, but spacecraft big enough to carry humans this energy leak is catastrophic.

If the rate of increase is to the power of something between ten to thirty this would be sufficient to end the world. You can easily check how of a catastrophe you want by doing a few calculations. Just adjust the values to suit the outcome you are seeking.

This answer recommends focusing on what you to achieve and doing it in a straightforward and simple manner as conceptually possible. Don't overthink the problem. Don't worry about what you don't want.

Remember you are practising what is best called "rubber science" or the science as it is usually used in science-fiction. The important rule of rubber science is never try to explain more than you know.

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    $\begingroup$ Thanks for the time and thought/input about writing this in general. This echoes some other (very valuable) points about not overthinking this/a little hand waviness in sci-fi is nbd. I'll definitely be re-reading this answer later and consider it in my writing attempts. $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:59

For background, this story begins in ... kind of irrelevant to the story... yadda yadda ...

Yeah, nobody cares. Or at least, I don't see anything relevant to the question.

They have a firm grasp on what we now describe as anti-matter ... to achieve faster than light travel, not by a warp drive, but by literally breaking the light barrier ... clearing the space in front of the ship of all matter by absorbing it and converting it to fuel nearly instantaneously.

OK, got it.

We can do this with a few (well, six) assumptions:

  1. there are more than three spatial dimensions, but the higher ones are "curled up" as speculated by various superstring or M- theories.
  2. your science director has found a way to use antimatter to partially and temporarily unfurl one or more of these dimensions, giving a localized bubble of effectively-higher-dimensional space inside normal 3 (or 4) space.
  3. we live in a metastable false vacuum
  4. there is another false vacuum state nearby which is metastable only while those higher dimensions are unfurled (and collapses back to our usual metastable vacuum when those dimensions are not being actively held open at significant energy cost)
  5. this other vacuum state annihilates normal matter at the boundary in such a way that the energy released can be used to prolong the local dimensional unfurling
  6. the speed limit is higher in the unfurled dimension than in regular space, so the false vacuum bubble can effectively propagate through normal space faster than light would allow

This gives you the option of claiming they were working on an antimatter-powered Alcubierre drive, but experiments failed due to its energy unexpectedly dissipating into (and temporarily unfurling) higher dimensions.

It gives you a way of annihilating matter in front of the bubble, the possibility of a bubble losing control (or popping), and the existential threat of accidentally triggering a full vacuum collapse. Conditions inside the bubble are wholly up to you.

Maybe point 6 (the actual FTL bit) is true in principle up to a certain energy density, at which further dimensions unfurl - dissipating your energy and/or triggering a full vacuum collapse.

This point (6) is probably the hardest to make convincing, although the same sort of claim is easily allowed when hyperspace is outside normal space, rather than being embedded inside it. Certainly the laws of physics are broadly permitted to differ in a different vacuum regime (so conditions inside the bubble really can be whatever you want)

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    $\begingroup$ Fair on your first quote, just thought if my thought process was outlined it might influence answers. Thanks for reading through and giving a thorough answer regardless! $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:29
  • $\begingroup$ Honestly I bounced off the wall of text a couple of times, and then worked backwards until I found something relevant :) $\endgroup$
    – Useless
    Aug 7, 2020 at 22:06

Perhaps something along the lines of John Scalzi's "Skip Drives" from the Old Man's War novels?

The skip drive, as explained several times in the various novels, most completely in book 1, allows for seemingly-instantaneous travel between points A and B. However the ship doesn't move at all, it simply disappears into an alternate universe, while simultaneously an identical ship arrives at the point of destination in the universe it just left. This is, naturally, a crazily unlikely event, but it's a quantum universe/multiverse so not IMPOSSIBLE. Due to (as the books say) universes wanting to keep that level of improbable events down to a minimum, the ships leave/enter universes that are fundamentally identical to their old ones, and the arrival point of the ship is inconsequential because a ship arriving from another universe is the "hard" part, where it arrives isn't that big a dea). Maybe a few atoms are in different positions than they were in your old universe. There are rules about it, like there being some maximum theoretical "skip horizon" that's so far out nobody cares, and that you can skip in close to a planet but need to be away from it to initiate a skip, but those are the basics that matter for you I think.

I found this version of FTL super interesting for a whole host of reasons, not least because I'm a fan of multiverse theory. Maybe your hero stumbles onto identical math, but with one fatal flaw. Nothing replaces you. So your hero's ship tears a massive hole in space-time which isn't filled by anything, with REAL bad results. Maybe there isn't a multiverse? Maybe there is and it turns out you can't "force" a nearby alternative universe to send a replacement ship? Who knows! Earth is doomed either way!

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    $\begingroup$ Doesn't really fit my needs for the plot, but I like the idea/thanks for posting! $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:55

Space pump

Why waste your time and energy traveling tediously through space? If you want to be somewhere else, just take all the space between you and your destination and move it behind you. It's basically a propeller or jet, but the medium is space itself. Artificial gravity can be achieved by routing a small amount through the ship itself, while pushing most of it around the sides. Moving space around shouldn't take much energy if there's not that much matter occupying it. (This requires a distinction between "space" as the phenomenon that keeps everything from being in the same place, as opposed to the measurement system we impose on it.)

AFAIK, this doesn't have a well-known precedent, so you can pretty much make up the rules as you go along. What's the penalty for going through a planet? Who does it affect? It's intuitive enough that you can maintain suspension of disbelief while pretty much making up all your plot points from whole cloth.

  • $\begingroup$ Novel idea (at least to me!) +1 $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:54

Lets look more carefully at what Einstein said.

You get some very strange results but relativity does not actually prohibit FTL travel. Rather, it says you can't accelerate to FTL speeds. That does not preclude some sort of drive that converts the whole ship to tachyons--which can no more slow down to lightspeed as we can speed up to lightspeed.

As for something going wrong--two things come to mind:

First, you're converting the whole mass of the ship. Maybe something doesn't scale right, rather than jumping to tachyon space you made a total conversion bomb.

Second, the drive works as advertised--but the jump field expands beyond the ship. It was believed it would simply peter out in empty space but in reality the field extends until enough matter has been grabbed to expend the energy. It's not a sharp dividing line, either--as the field weakens it starts grabbing some particles and not others. In small scale testing this just grabbed some of the atmosphere around the test body but when it's a whole starship in space that's not enough, it ends up tearing up whatever is around (for a large definition of around, it takes a lot before the interplanetary medium dissipates it!) quite catastrophically--atoms randomly lose subatomic particles, the result is usually not the original element and probably radioactive, if a lot is missing it's exceedingly radioactive. You get a big chemical boom that blazes in the gamma spectrum.

Second, there is the problem with time travel. By the choice of reference frames you can end up with a FTL ship ending up in the past. There is a solution here, though: Something about the drive defines the reference frame. Relativity does not require a consistent reference frame but that does not mean there can't be some sort of externally imposed reference frame. Consider the hyper drive of so many sci-fi stories--you move from our universe to another in order to attain FTL speeds. Suppose the transition requires zero velocity relative to the interface between the universes. Presto, no time travel paradoxes.

For something to go badly wrong--oops, the junction isn't as flat at the scientists believed. It's flat enough a small scale test craft works as it's supposed to but a whole starship extends too far from the generator, the universes diverge too much by the time you reach the edge of the ship that the jump doesn't proceed as it's supposed to. Perhaps this just results in the atoms of the ship being ripped apart, perhaps something far worse happens. (I'm thinking of Asimov's The Gods Themselves where the mass that comes across the transit brings the properties of the universe with it.)

While we have zero hints as to how either of these might be possible neither is prohibited by current physics.


I'm surprised nobody has mentioned the solution of Mass Effect yet. The phlebotinum of the setting is a substance which can increase or decrease the mass of itself and objects around it by applying electrical current; which is what the series was named after.

This allows FTL because you can give your entire spaceship negative mass. The famous E=mc^2 equation, in its expanded form, only postulates the lightspeed barrier for objects with positive mass: the energy required to increase a certain mass to a greater speed approaches infinity as the speed gets near c. Photons, and several other particles, are massless, and according to the same principle are required to travel at c.

And particles with negative mass? This theoretical substance is open to much speculation, but it is reasonable to suppose that something with negative mass is obliged to travel above c. So you fire up your mass effect engine, and as the ship accelerates it gets lighter, crossing the lightspeed barrier when it is massless, and then continues on above c with negative mass.

Just adopting this theory for your setting will probably draw comparisons with the Mass Effect setting, but the general idea is applicable: take one of the equations prohibiting what you want to achieve, and try to flip a sign using a substance or field with exotic properties.

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    $\begingroup$ This is also how the Heechee drives in the Gateway books worked $\endgroup$ Aug 10, 2020 at 12:45
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    $\begingroup$ Thank you! Will be incorporating this in some form $\endgroup$
    – TCooper
    Aug 10, 2020 at 18:31

Your question is not going to have an answer as posed, because you've already worked out an extremely detailed outline of the story, which is inconsistent with well-established principles of physics.

But if all you want is an answer to the more general question posed in the title, then I can think of a couple of general types of possibilities:

(1) Wormholes.

(2) A device like the Star Trek transporter, but with the signal being sent using tachyons.

Both of these are consistent with all the known laws of physics. Both of them lead to time-travel paradoxes, because any FTL technology is automatically also exploitable as a time machine.

In #2, you have the problem that tachyons don't actually seem to exist.

For a more detailed discussion of the physics, see section 4.7 of my special relativity book, http://lightandmatter.com/sr/ .

  • $\begingroup$ The detailed outline is what I have, I'm not opposed to changing it - but fair enough. Thanks for the link and your time. $\endgroup$
    – TCooper
    Aug 7, 2020 at 19:53

In order to travel faster than the speed of light in normal space you're going to have to revise a lot of current physics. With the rules as they stand the only way to get around the light-speed barrier is to modify space... a warp drive, one way or another.

Since as far as we can tell the speed of light is inviolate under the rules as we know them, the most obvious answer is to change the rules.

Back when the CERN super-collider was first fired up there was a little talk about the possibility that the proposed experiments could cause a localized change in one or more of the fundamental rules of physics. The problem with this is that there is the potential for this to cause a catastrophic cascade reaction that could destroy the entire universe - maybe at light speed, but possibly at unbounded speed.

Now imagine that your main character has developed a method for producing very specific changes in the fundamental laws of physics at will. In lab conditions he has managed to modify the fundamental rules in a small volume of space in such a way that the normal mass interactions are replaced, using a different set of interactions that are not limited by the light speed barrier. While the field is active an object is essentially massless and can be accelerated to very high relative speeds with very small energy expenditure... solving not just the speed of light problem but your energy issues as well. He's even figured a new set of physical laws that will make everything feel normal in there, just disconnected from the rules in the normal universe. A true feat of genius.

At the boundaries of the region of altered physical law there is an interface layer where physical laws are essentially chaotic. While this is initially of some concern to the scientists it is soon discovered that the interface layer is only a few nanometers in depth and doesn't seem to produce much more than an interesting visual effect and a few stray exotic particles.

What isn't obvious is that when the generator is in motion the interface zone on the trailing edge of the field increases in size depending on how fast the field is moving, like the wake of a boat in motion. At around 14 times the speed of light the interface zone destabilizes and ruptures, leaving a wake of chaotic physical law changes behind the vessel.

Imagine how it would feel as you pop out of your FTL test flight somewhere near the orbit of Mars and looking back towards Earth. A few light seconds away you see evidence of a massive exotic particle burst and as you watch the photons from further and further away arrive. From your perspective it looks like the fuse of some great demolition explosive, lit in the exotic particles of your FTL wake. It races back along your path towards your departure point in orbit around Luna and you watch in horror as first Luna and then the Earth are engulfed by the phenomenon, shattered, torn, crushed and then turned into a ball of glowing plasma.

When the boiling wake of uncertain physical laws finally reaches you will you give yourself up to it or turn on the drive and run, knowing that you could be dragging a trail of annihilation across the universe by doing so?

  • $\begingroup$ This is essentially how the Warp Drive in Star Trek works. Except, of course, that the "boiling wake of uncertain physical laws" only takes effect once you reach Warp 8, and even then it doesn't do too much damage. $\endgroup$
    – The Daleks
    Aug 9, 2020 at 23:50
  • $\begingroup$ @TheDaleks I took the term "warp drive" to mean "a drive which works by warping space" which is what I always thought was happening with Star Trek's warp drives. Changing the fundamental laws of nature is a bit different to that :) $\endgroup$
    – Corey
    Aug 10, 2020 at 1:06
  • $\begingroup$ It's a mixture - it warps space to create a roughly bubble-shaped micro-universe around the ship, within which the laws of physics allow FTL travel. If the "warp factor" (how much you are warping the laws of physics) exceeds a level of 5, you start tearing up spacetime. As a result, most Star Trek ships have two speeds - a painfully slow warp 4, and an absurdly fast warp 8/9 for emergencies (or if you just want to get home from the Delta Quadrant and don't care how big of a "boiling wake of uncertain physical laws" you leave behind :) $\endgroup$
    – The Daleks
    Aug 10, 2020 at 11:52

Imagine you've invented some way to carry infinite fuel on what is otherwise an ordinary rocket. You get into orbit, plan a trajectory to Alpha Centauri, fire up the engines, and away you go.

At some time you reach light speed, and so there's no point in running the engines any more, because you just can't go any faster, right?

No, that's not how it works. You can in fact accelerate as much as you like, given that you still have some means to do so. The more thrust you make, the faster Alpha Centauri gets bigger in your window, and the less time will pass on your watch as you ride on the ship until you get there. If you want to make it to Alpha Centauri in 1 day elapsed on your watch as a passenger you can do that now, with our current understanding of physics. All it requires is:

  • some means of generating enough thrust, and
  • some means of not entirely obliterating the spacecraft and the occupants with the tremendous acceleration and deceleration required.

It's pretty easy to imagine solutions to these issues in the future.

The "problem" is that to observers on Earth, everyone on the spacecraft has stopped aging, and the craft doesn't go faster than light. And to the people on the spacecraft, everyone on Earth, and a thousand generations after, have lived and died in the blink of an eye.

In other words, the light "speed limit" is not so much a problem of speed, it's a problem of time.

So naturally, an advanced civilization has developed different ways of thinking about and managing time. It's not such a problem if the trip is 10 minutes for you and 10,000 years for your friends if medicine has solved aging, and this kind of travel is commonplace for everyone. Maybe these new ways of thinking about time are what necessitated the change to the new calendar.

Astronomical timescales, like the birth and death of stars, suddenly becomes relevant to everyday life to such a civilization. But you've also got interstellar travel in the garage, so it's no big deal. Trash pickup is on Tuesday, and on Wednesday it's a little dark for a bit while a crew hauls away heavy elements from the star so it doesn't go nova. Extreme time dilation creates issues, but dealing with these issues is commonplace for an advanced civilization because the processes are understood and there's a system for dealing with issues proactively.

...until someone proposes a new technology that enables even higher speeds and more time dilation. An error is made in anticipating the consequences, and "whoops"...


If you cant "Warp" spacetime, what other options do you have. The light speed barrier limits matters interaction at lower than light speeds. All faster than light travel distorts spacetime in it's overall common laws.



We have pretty solid understanding of what happens when particles approach c in particle accelerators, . We know to the limit of our measurements than General Relativity holds up. There is no "Faster Than Light" movement, that is mathematical impossibility if you use General Relativity to describe the movement. Sort of like, if you use [x, y, z] vector to describe the position of an object in a computer game, that object can't be in your pocket.

However, all these measurements have been done on particles accelerated by outside force, such as electric and magnetic fields. There's no way to have a particle with plain Newtonian reaction drive (AKA "rocket") to accelerate it. If you have something big enough to be accelerated by the rocket, there's no hope of reaching any kind of high speeds with internal fuel, thanks to the Tyranny of the Rocket Equation: the type of fuel and rocket engine determine how large change in velocity you can have, and adding more fuel does not help because that fuel makes you heavier so you use that extra fuel to accelerate the increased mass.


In your story, something beyond current physics have been theorized, experimented with, the re-theorized, and finally proven over decades of research:

  • Many of the relativistic effects measured on particles and larger objects such as laser sail probes sent to the deep space at significant fraction of c are actually result of the method of acceleration.

  • An object "knows" how it got its current speed, and that is what causes the relativistic effects we observe. There is a "relativistic charge" it carries with it, much like electric charge, as a fundamental property obeying its own laws. The "light speed barrier" is just an artifact of this charge, not a fundamental property of space-time. The maths all work out, and no paradoxes remain.

  • Causing relativistically asymmetric acceleration using both external forces and internal propulsion at so-called relativistic speeds allows creating mass which has its relativistic charge altered. This is incredibly expensive, as getting a big enough rocket engine to high enough speed with external power (laser sail probably) is a huge project. It's also just plain hard, as despite the enormous acceleration, the whole thing needs to be precisely controlled or the "relativistic charge" dissipates before becoming stable.

  • But once it can be done, once you can create mass with different relativistic charge, the benefits are mind-boggling. The different relativistic fields caused by the charge combine in much the same way as electric and magnetic fields do, so it is possible to build a space ship with "relativistic core", and achieve effects which "break" our current understanding of General Relativity.

  • FTL is one of these effects. At least in theory, you can simply just go "faster than light" with finite acceleration, if you have the right relativistic field configuration. It's just that nobody has really figured out just how to build such as ship. There has been countless hours of simulation on supercomputers, and catastrophically failed experiments, but nobody has managed to create a working model, let alone a working prototype. Until now.


Considering that the Star Trek franchise coined the term "warp drive", let's look at other technologies that they did not consider to be warp drive:

  • Wormholes are tunnels connecting parts of space-time. Voyager 6 was transported to the far side of the galaxy by a wormhole, to become V'ger, in The Motion Picture. The transit rights through an unstable wormhole was auctioned in the TNG episode The Price. The entire premise of the Deep Space Nine series was a space station guarding a stable wormhole. And several episodes of Voyager utilized wormholes.

  • A displacement wave is described as "a polarized magnetic variation". The Guardian of Forever in the TOS episode City on the Edge of Forever produced displacement waves that could transport people through time or space. In the premiere of Voyager, an entity called The Caretaker had a space station that he used to bring ships across the galaxy, including Voyager.

  • A soliton wave is a wave that can travel faster than light. The TNG episode New Ground portrayed an unsuccessful attempt of a starship riding such a wave.

  • Several advanced species developed long-distance transporters. Agent Gary Seven used one at the start of the TOS eposode Assignment: Earth. The Iconians developed a gateway that they used 200,000 years ago, which was re-discovered in the TNG episode Contagion.

  • Q had powers to alter reality, including sending the Enterprise across the galaxy to meet the Borg in Q Who. It's arguable that other alien species (especially in several TOS episodes) had similar powers.

There are also instances of faster-than-light travel using warp technology, but without warp engines (Borg trans-warp conduits) or in an unconventional way (the TNG "Traveler").


Some mostly stupid ideas I had-

Idea 1-

  • turn your ship to photons.
  • fly away at light speed.

Of course, this is only light speed, but the next idea might solve that. Or maybe it just makes it worse.

Idea 2-

  • make up some vaguely explained engine. that's what I did here(It says light speed, but you can make it FTL).

Idea 3-

  • something like what happens in Skyward. (No idea how it works. Probably won't work for you, but maybe it can help. )

Idea 4-(falls partly under Idea 2)

  • decide what you need(FTL engine)
  • make up some vague explanation that somewhat follows the laws of science(talking about radiation and/or atoms and/or nuclear generators and/or made up sciency sounding stuff here is a good idea since it sounds confusing but strangely correct at the same time), or since yours is so far in the future, you can make up your own laws of science.
  • since you want yours to fail, add in something like:

any deviation in the (sciency whatnot) could cause a total system failure, including but not limited to(list your desired consequences here)

or similar

  • Just for fun, you could throw in a California Proposition 65 Warning, if that's around in your story.

  • Just have fun with it. Even if you need to change it later, add in another sciency spiel that nobody will understand. I don't know about everyone else, but I don't read most of the sciency explanations in books if it's longer than a paragraph.


Quantumn Drive. We exist at all points in the universe at the same time just in different levels of probability (essentially the basis of quantumn computers). You need to change the probability.

  • $\begingroup$ That's not the basis of quantum computers. The basis of quantum computers is the qubit, which can be 1 and 0 at the same time. $\endgroup$
    – F1Krazy
    Aug 8, 2020 at 14:16
  • $\begingroup$ This is an interesting concept, and the tenderest seedling of what could be a good answer. Please elaborate! Check out the tour and help center so you can get a better idea how to answer (and ask) questions here. $\endgroup$
    – elemtilas
    Aug 8, 2020 at 14:16
  • $\begingroup$ I think it was first mentioned in the hitchikers guide to the galaxy as the infinite probability drive. $\endgroup$
    – user78679
    Aug 8, 2020 at 18:39
  • $\begingroup$ F1Krazy - qubits are not neccesarily 0 or 1, your forgetting superposition. There is a probabality they may be either be 0 or 1 but they can also be in another quantumn state. Anywhere between 0 and 1. $\endgroup$
    – user78679
    Aug 8, 2020 at 18:46

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