Sci-Fi Tropes #1: Faster-Than-Light Travel
As the great Douglas Adams once put it, “Space is big.”
Over the decades we’ve learned a great deal about our universe just from the various technologies we’ve placed in orbit around the Earth (Hubble Space Telescope) as well as what’s deployed on our planet (various observatories such as the Five-hundred-meter Aperture Spherical Telescope in China). The more we learn about the universe and our place in it, the more we realize just how inconceivably large it is. The scale of it - about 91 billion light years in diameter - is honestly incomprehensible to most, if not all, of us. We understand the numbers and can certainly do size comparisons to add some perspective and make us feel insignificant, but it all boils down to one simple phrase:
“Space is big.”
When it comes to writing science fiction, the idea of finding a way to move humans through the universe at incredible speeds is nothing new. The earliest mention of the "faster-than-light travel” (it’ll be abbreviated as FTL from this point on!) idea in science fiction was in Camille Flammarion’s “Lumen,” written in 1872.
In terms of the presentation of FTL from a technical perspective, where the application of science was concerned, we look to John W. Campbell’s “Islands of Space” which was published in 1931. (click here to learn about Islands of Space and other candidate stories)
However, the mere concept of being able to travel instantaneously between two points - effectively FTL - was explored in a science fiction novel (arguably the first ever science fiction novel in history) by Johannes Kepler, “Somnium” - it was written in 1608 and published in 1634.
In other words, we’ve been thinking about this for a long, long time. However, between the numerous observations made by scientists over the centuries, Einstein establishing the Special Theory of Relativity, and our general lack of evidence to suggest otherwise, it is clear that based on our understanding of the universe today, breaking the light speed barrier is impossible.
That hasn’t stopped filmmakers and authors from exploiting the FTL trope in a myriad of ways.
Even among those that don’t actively read science fiction novels or even consider themselves fans of the genre, the FTL trope is ubiquitous in our culture. Almost everyone can reference Star Trek or Star Wars as prime examples of FTL in action, even if they haven’t watched either series. Who can blame them? The idea that we’d be able to advance to the point where travelling between the stars is as simple as jumping in your car and commuting to work is fantastical, firing off the imagination into the wondrous.
The moment you start exploring the world of science fiction, it wouldn’t be long before you stumble upon FTL and its many varieties. Let’s explore some of them, shall we?
One of the two most well-known forms of FTL in fiction, warp drives manipulate space-time around the host ship in a way that allows it to propel itself forward many times faster than light. There’s usually some form of exotic fuel involved, but in the end this can be considered one of the simplest forms of FTL out there. You rev up your FTL engines and go.
That said… this might be the most viable way for us to travel the universe in the future. The concept is still very theoretical, but check out the Alcubierre “warp” Drive - a way to “bypass” the light speed barrier based on actual scientific data and research.
Now we’re getting into the more interesting variants of FTL.
Hyperspace is best thought of as some otherdimensional region of our universe (or maybe a different, parallel universe altogether) where the laws of physics allows movement of a ship to exceed the speed of light. Alternatively, the overall distance traveled in the parallel dimension is simply much shorter than it would in our universe (ex: one mile in hyperspace could equate to one million miles in our universe). At the same time, your placement in this hyperspace mirrors that of our universe - this allows the traveler to enter hyperspace, travel a couple of minutes there, and upon re-entering their home universe be several hundred or thousands of light years away from where they started.
Because of the separation of our universe and hyperspace, it is possible to create plots that involve the adverse interactions that may be possible while in hyperspace. One great example that is at the top of my head is “Immaterium” from the Warhammer 40k series. Another, more popular, example would be from the sci-fi TV show Babylon 5.
And, of course, Star Wars uses hyperspace as their primary mode of galactic travel. How else can you make the Kessel Run in twelve parsecs? (Some scientific context: a parsec is a real unit of measurement, one unit of which equates to about 3.26 light-years.)
If you want to get somewhere fast, nothing’s faster than instantaneous travel. This is the essence of the jump drive. You have an engine which, after some amount of time warming up, “jumps” you from one point in the universe to the other in an instant.
The biggest example of jump drives can be found in The Foundation Series by Isaac Asimov. In the world of TV, Battlestar Galactica is the place to look for jump drives in action. In film, Event Horizon - one of my favorite sci-fi horror movies of the 90s - uses a jump drive (simply named “the gravity drive”) to be able to jump to any point in the universe.
One notable element commonly used with jump drives are limitations. A common one, seen in Battlestar Galactica and Event Horizon, is the need to “warm-up” the engines that power the jump drive before it can actually be used. This can open the door to dramatic moments in literature where the length of time needed to jump can be a critical factor in escaping a lost battle, for example.
Tear a hole in space-time and what do you have? Okay, it’s not that simple - but sometimes it is, depending on what you’re reading or watching.
The idea is to have two points in space that are connected to each other via a “fold” in space, thus reducing the distance between those two point to effectively zero, regardless of how far apart they physically are.
The concept of a wormhole has some theoretical backing to it, but like the Alcubierre Drive, the technological hurdles needed to fully explore this are currently well-beyond our capabilities today and there’s little evidence to suggest that they exist in nature.
In some ways, wormholes can be compared to jump drives in that they can allow near-instantaneous traveling between two points in space. However, one notable difference with wormholes is that they can be naturally occurring phenomena which can then be exploited.
The Fall Revolution series by Ken MacLeod is my best example in literature for the use of wormholes. It was really fun because of the “paradox-free traveling” that it allowed. In film, Interstellar uses a wormhole as a way to allow humanity to explore a star system in a different galaxy.
When you are writing your story, what matters in the end are the characters and the plot. Any technologies that are used are there to serve them. Therefore, in the case of writing sci-fi, providing just enough technobabble to make your FTL tech plausible is all that’s needed, especially if the technology itself isn’t the crux of the story.
Of course, there’s always the alternative to FTL technology: not using it at all. Is it possible to create a galaxy-spanning empire without the ability to break the light barrier? Though they are few and far-between, one novel to check out is Alastair Reynolds’s House of Suns which does exactly that: a galaxy-spanning empire that exists without the use of FTL.
Which is your favorite form of FTL travel? Are there any books, TV shows, or movies that you’d recommend that utilize FTL technology? Share below!