A Newtonian Universe
Stirring up trouble
I participated in a Twitter chat last Friday with fellow science-fiction/fantasy writers, in which it was suggested by one commenter that it would be a good idea for a writer to study science in order to better his or her writing. I made the perhaps foolish comment that if any writer were to really study physics, they would quickly learn that most of what they have been reading and writing is impossible.
This caused a bit of a debate, to say the very least.
Faster than the speed of light
But it’s a defensible statement; I just needed more than 140 characters to do it.
Start with space travel in science fiction. It’s understood that everything in space is a great distance away from everything else in space, so the only way to go tooling around the galaxy in space ships is to posit the existence of faster-than-light travel (FTL for short). The problem is FTL is impossible.
It’s easier to appreciate this if you look at time and space as parts of the same thing, i.e., spacetime.
Approach #1: Imagine two buckets, one called space and one called time, with enough water to fill only one of the buckets. Sitting on Earth right now, let’s say 1/4 of the water is in the space bucket and 3/4 is in the time bucket.
Got it? Okay, now: per Einstein, the faster you move through space the slower you move through time, so on a rocket ship moving away from Earth at great speed you’re going to be moving some of the water from the time bucket and into the space bucket. (It’s the same water because space and time are part of the same thing; there is a direct trade-off.) The closer you get to the speed of light the more water is added to the space bucket and the less water there is in the time bucket.
When you reach the speed of light all the water is in the space bucket and none is in the time bucket. And here’s the problem: you’re out of water, and buckets.
Approach #2: the faster you go the greater your mass becomes. At the speed of light you become infinitely massive. There is nothing beyond “infinitely massive”.
Approach #3: the cosmic speed limit isn’t really the speed of light: it’s the speed of particles without mass. There is no such thing as negative mass objects, so there is no such thing as particles that can travel faster than that speed.
There is no Stardate
Here’s another problem: time is a strictly local concept. There is no non-local “now”.
As stated above, the faster one moves the slower one passes through time. But this statement presumes the existence of an objective “time” one can pass more slowly through, which is inaccurate. It’s more precise to say that time passes more slowly for a rapid traveler from the perspective of another observer.
What this means is, the Starship Enterprise’s five year mission to explore strange new worlds may be five years of ship time, but it’s thousands of years–conservatively–of Earth time.
There is no Stardate to enter into the captain’s log, because a common “date” would imply a universal measure of time, and there is no such thing. In Einstein’s universe, time and space are both malleable and subjective.
Tooling around in a Newtonian universe
And that’s the real problem with modern science fiction: most of it is set in a Newtonian universe, rather than an Einsteinian one. In Newton’s universe you can travel as fast as technology will allow, time is an objective thing, gravity is a force that can be countered, a laser is something that can be dodged, and so on.
Ah, you might say, Einstein could be wrong! Or better, there are things we simply don’t know yet that could make these things possible!
Okay, but here’s the problem: if you’re writing science fiction and positing that one of the laws of thermodynamics is incorrect, or that Einstein’s theories are incorrect, you’re not writing science fiction any more. You’re writing fantasy. There may not be any magic, but the science you’re using is impossible, so it may as well be magic.
Mutants aren’t real
This doesn’t end at the edge of Einstein, either. Basically every steampunk invention ever imagined is impossible–usually because someone’s violating the second law of thermodynamics, which expressly disallows perpetual motion machines. Likewise, every super-powered comic book character violates the same law. (How much food would The Flash need to eat to run that fast? The energy has to come from somewhere. When Iceman creates an ice ramp to travel on, where is the water coming from? And on a separate note, by what mechanism does Superman fly? There’s no propulsion: he’s just floating. It drives me nuts that nobody even tries to explain this.)
I have seen it written–and I have written it myself–that the difference between science fiction and fantasy is whether one attributes the fantastic to magic or to science. But the truth is, once you get past the masters of hard science– your Asimovs and Bradburys and Clarkes— it’s all fantasy. Whether the writer knows it or not.
Oh phooey! There go all my delusions down the drain! 🙂 I think this is where the whole Science Fantasy vs. Science Fiction thing comes in, though I am far from claiming to be a Science anything snob. I would just say it has to do with basing things on some future technology (whether scientifically viable by today’s standards or not). Who knows? We might discover that the laws of physics aren’t really laws at all. Then again maybe I should just stick to FANTASY where I belong.
I tried to stay away from the “future technologies” argument, because that’s a bit more malleable and open to possibilities. My larger point is that ignoring things like “time is local” and “there is no way to travel faster than light” is a little like setting something underwater and pretending it isn’t wet.
Then there’s the issue of theme. I write about mermaids and dragons- so I’m told I should call it paranormal (or fantasy). But I explain their occurrence via made-up science. Simply writing fictional science does not make me a science fiction writer. I also think there’s a mild male author= science fiction while female author = fantasy/paranormal bias.
Immortal presents a similar problem: magical creatures, no magic. But hey, I’m a dude, so maybe you’re right and I can get away with not calling it fantasy.
You can totally get away with it because you’re a guy! I write romance, and sci-fi romance is a hard sell. So even though my mermaids are being experimented on by a biotech company- I need to call it paranormal.
But aren’t you going to market Immortal as “literary fiction” anyway?
Literary fiction? God no. The closest match for Immortal is contemporary fantasy, even though there’s no magic or romance. And I’m a dude.
out of curiosity, was this by chance in response to what david_haddon and twilight2000 were saying? i only caught some of it as you were actually conversing but it makes me wonder . . .
The original statement I refer to at the start of the blog post actually came from (I think) @Jlichtenberg. Everything that came up in discussion after that was entirely my fault for lobbing a “you know, none of this is possible” grenade into the middle of the room.
You say “mutants aren’t real” but your examples are all Superheroes – Genetic mutancy (more along the lines of Xmen) makes more sense – might still be bad science – but it would be a different type of science (and I know even less about genetics than physics ;>)
Iceman is a mutant. But okay, what is the energy source of Cyclops’s concussive beams? What body part allows Nightcrawler to teleport? What is colossus’s human skin made out of that it can transform into an impervious metal and what else within that transformation gives him superhuman strength instantly? Quicksilver has super-speed just like Flash, with the same problems.
Genetic mutations are real, but they very, very rarely beneficial. They also happen incrementally, and don’t result in super powers.
lol was just curious. it’s a good article, btw. am going to retweet just so’s you know and i look forward to this friday’s scifichat with much anticipation 🙂
Even with that, faster than light travel may be possible, aherm, not in a Newtonian sense, but in the sense that an object can appear in one objective place, then move to another objective place faster than light can move between those two places.
You know, wormhole travel, hyperspace travel, the “folding universe” theory of travel from Event Horizon. We’ve come up with lots of theoretical ways to get around the limitation of lightspeed travel.
Didja see the newest thing, that our universe may exist inside a black hole?
I skipped the wormhole argument, for a couple of reasons. It’s true that they’re theoretically possible in Einstein’s universe, but it’s also true that space travel isn’t depicted that way. The Enterprise has those stars flying past, after all, and there is clearly still travel going on in “warp drive”. Even when a wormhole was depicted– in Voyager, if memory serves– it was presented as an unstable tunnel, which was inaccurate.
In more concrete terms, what is understood about wormholes is that there has to be a stable start- and end-point. It’s something that could exist theoretically, but not thrown up by a space ship and used as a comprehensive method of travel.
And finally, if I’m remembering correctly– and I might not be– the energy required to create one may be more than all of the energy available in the universe, which would make it effectively impossible.
Speaking as a hard sci fi guy, the flip side is that if you think about what your gadgets do (even if it’s impossible by known means) you also have to ask what else they do, and what else needs to happen. George Scithers gave a great example: if Superman leaps a tall building at a single bound, you’re still working hard-sf as long as he kicks a hole in the sidewalk in one direction and digs an equal hole where he lands. Or from Jerry Pournelle: If a Belter prospector has a ship that puts out enough power (not energy, power=energy/time) to move from asteroid to asteroid in a period of a few weeks, its exhaust (which it has to have, there are no reactionless drives known) would be on the order of a kiloton/sec. So why doesn’t some poor starving prospector just fly back to Earth and say, “Put a gazillion credits in my account or I’m pointing my exhaust at San Francisco?” (Or “I’ll burn an exhaust trail all the way from Boston to Atlanta”, take your pick). Aha. Now you have the TransMartian Line of space stations with interceptors … but then what stops General Plot-Device from diverting forces from the TML to stage a coup? And why are you mining the asteroids when the delta-v (energy required to change the orbit to bring the stuff back to Earth) is so much bigger than the amount you’d use to just gasify all the old landfills and use magnetic sorting (same tech that’s been around for making a-bombs since 1943) to bust them into the 92 or so naturally occurring chemical elements (there aren’t going to be any more, and there’s no process by which an asteroid would acquire a lode of, say, Element 117). When you’ve got enough of those things explained, you suddenly have yourself a skiffy world, all full of skiffy goodness, that other people haven’t done before or to death.
This works even with impossible gadgets. My “springers” from my 1000 Cultures series — instantaneous transporters, which as Gene points out implies that under our relative and local time there has to be an absolute time — are stargates, of course, but if you have those, you also have vacuum cleaners that transport dust straight to the dump, hotel rooms with no doors (much better security!), never-ending ski runs (ski in at the bottom, out at the top, till you have all the velocity you can handle, and my favorite moment in one book — the hero tips over a garbage springer and hides behind it in the middle of a gunfight, thereby causing all the bad-guy bullets to emerge into the municipal recycling system.
Don’t give up and say “impossible” — but do think “What else is possible?” “What else would they do?”
If a fire spell always works, would anyone know what flint and steel were, let alone invent matches? If there are flying dragons that people ride, how much do you have to feed those guys, and how do the peasants feel about it? (Peasants often blinded war-charger colts in our middle ages because they didn’t want to give up half their crop to feed a bunch of horses; if Castle Bodacious has a flock of twenty dragons, how far away do the peasants bring food from? And why isn’t some sturdy peasant rebel poisoning the grain, or breaking wingbones on dragonets with his hoe? There’s got to be a reason …)
Anyway, if you just want a stock sci fi or fantasy set, I guess you can stick in things you’ve seen from movies and read in books; but if you want something new, ask that critical question … “If I’ve got this, what else do I get?”
“You can’t do one thing.” John W. Campbell
A man after my own heart. Rather than borrow someone else’s idea for what travel might be like, learn the science and figure out what makes sense. Bravo.
[…] (The Original post with comments can be found on Gene Doucette’s blog – https://genedoucette.me/2010/07/26/a-newtonian-universe/) […]