A crass animated television show on Adult Swim isn't the first place you'd think to turn for realistic scientific ideas. Yet, Rick and Morty finds a way to sneak in more real-world science than your average issue of Nature, between copious jokes about buttholes and existential despair.
Of course, not all of the episodes are focused on lampooning cutting edge technology and hypotheses. Take this week's episode, "The Old Man and the Seat," for instance, which focused almost entirely on Rick's particular bathroom habits.
Despite the occasional detour toward literal potty humor, though, the show's real bread and butter often comes down to scientific deep-cuts. Across its three seasons, with the fourth airing now, Rick and Morty has touched on dozens of concepts that have their roots in actual scientific inquiry, from the multiverse to hive minds and mech suits. Just to name a few.
But none of those adventures happen at all if Rick can't traverse existence with Morty in tow. One of the ways he does that is by use of his ship, which, according to the Season 1 episode "M. Night Shaym-Aliens!," is powered by concentrated dark matter.
After finding himself at the mercy of nefarious aliens (nefarious being a variable term in the Rick and Morty world), Rick realizes he's been placed inside an artificial environment with a single purpose: Uncovering his recipe for concentrated dark matter, the fuel for accelerated space travel.
It's a secret valuable enough that the Zigerions are willing to invest vast technological resources to developing several layers of photo-real simulations to uncover it.
In the end, Rick gets the better of them, delivering a false recipe of two parts plutonic quarks, one part cesium, and a bottle of water. The result is not the promised concentrated dark matter, but instead, a deadly explosion. Zigerions may have incredible simulation tech but they missed a few key chemistry lessons. Cesium is highly reactive and reacts explosively when in contact with water. No word on the impact of adding plutonic quarks.
One is forced to wonder, however, if dark matter would actually make good fuel for a spacecraft.
WHAT IS DARK MATTER?
That is the question. The answer: We don't really know. In fact, we know a whole lot more about what it isn't. For decades, physicists have suspected there was more going on in the universe than we could see. Models of the way stars move give hints at a major player just outside our view.
This is something we've been grappling with for a long time, to varying degrees. The astronomy field has always been plagued with the knowledge that there is more out there than we can see.
Going back centuries, astronomers suspected a large, "dark" object in our solar system. We knew it should be there because of the gravitational pull it exhibited on other nearby objects, yet, observing it was beyond our technological ability at the time. That changed in 1846 when Neptune's existence was confirmed.
Each new discovery chips away at our ignorance and paints a clearer picture of the universe we inhabit. The continued existence of dark matter, in the modern context, only underlines how much we still don't understand, how much there still is to learn. Because things still don't add up.
In short, when we model the universe, the way things move and interact, and the way it expands, we just can't account for our observations with the matter we've been able to identify.
According to NASA, in order to make sense of what we observe, the universe needs to be made up of roughly 68 percent dark energy and 27 percent dark matter, leaving only 5 percent for the sorts of stuff we're familiar with.
We can't account for dark matter with black holes. The number that would be needed in order to fit the bill would result in gravitational lensing all over the place, and we just don't see that. Antimatter also doesn't work, as we're missing the sorts of radiation that would come as a result of matter-antimatter explosions. Basically, all the kinds of matter we know about, in the amounts that would be needed to account for the measured gravity, would have a corresponding signature we could measure. And, yet...
What remains is the conclusion either that we have a fundamental misunderstanding of physics, or there is some other form of matter that we've yet to identify. We've given that stuff, whatever it is, the moniker "dark matter."
That isn't to say scientists have no idea what dark matter is. In fact, all we have are ideas. It's possible that dark matter is, in fact, the normal sorts of stuff, only more difficult to detect; brown dwarfs could account for some it, white dwarfs, neutron stars, and, of course, black holes. Even still, it's unlikely.
The leading hypothesis is that dark matter is comprised of WIMPS (weakly interacting massive particles).
These particles are orders of magnitude more massive than protons but have weak interactions, hence the name, making them difficult to detect. There are also hypothetical particles that could fit the bill, but have yet to actually be detected (hence their being hypothetical). That's the sort of thing the Large Hadron Collider might uncover in future experiments, as it smashes protons together hoping to get a glimpse at exotic matter.
A heretofore undiscovered neutrino is another candidate. Neutrinos are common particles. So common that each of us is being bombarded with them all the time. But they rarely interact with matter. Approximately 100 trillion neutrinos pass through your body every second, but detecting them can be difficult. Most neutrinos will pass through you and the rest of the Earth before zipping back out into space without interacting with a single atom along the way.
In an experiment published in the journal Science, researches fired trillions of neutrinos, every second, at a detector for fifteen months. In that time, they measured only 134 interactions. They are incredibly stealthy.
Those scientists banking on a new type of neutrino as a dark matter candidate propose a particle that interacts with matter only by way of gravity. If such a particle were discovered, it would explain the excess gravity in the universe and our inability to see what's causing it.
COULD IT FUEL A SHIP?
That depends entirely on what dark matter turns out to be. If, in the end, we discover that dark matter is the same sort of stuff we're used to, it likely won't offer any new avenues for space travel. But if it turns out to be exotic, if it's something totally new, then it might open the door to some truly astonishing spacecraft.
Using conventional chemical rockets, a trip even to the nearest star would take so long as to make the trip hardly worth taking, at least for humans.
NASA is planning to launch a new spacecraft, the Parker Solar Probe, in December 2024. If all goes to plan, it will become the fastest spacecraft to date, clocking in at 430,000 miles per hour (692,000 km/h) at its top speed.
Even at that rate, that craft would take nearly 7,000 years to traverse the 25.67 trillion miles to our nearest stellar neighbor, Proxima Centuari.
The strides we've taken in exploring space over the past several decades are nothing to scoff at, but chemical rockets just aren't terribly efficient and, if we hope to get beyond our own neighborhood, we'll need something new.
That's where dark matter may come in.
Some scientists believe dark matter may be made of particles with no charge, called neutralinos. If that's the case, these particles would also act as their own antiparticles. And, based on what we do know about dark matter, chiefly its abundance in the universe, they'd be free for the taking.
From a practical standpoint, this means you could launch a ship with very little onboard fuel. Additionally, dark matter could be collected while in transit and made to interact with itself, creating antimatter reactions that are 100 percent energy-efficient. Compared to current engines, which operate at less than a percent fuel efficiency, such an engine would entirely change the way we move through space.
According to a paper by Jia Lui, a physicist from New York University, such an engine could accelerate a craft to near the speed of light in a few days. And, from there, not even the sky's the limit.
Whether or not we'll ever uncover precisely what dark matter is, or if it can be utilized for space travel, remains unseen. For now, Rick is keeping that knowledge for himself.
The good news for any Zigerions out there is, once we find it, you won't need any complex recipes to make it work.
Until then, we'll have to placate ourselves with the fictionalized adventures of a mentally unstable inventor and his grandson.