Note: This article contains major spoilers for Outer Wilds.

Last week, I talked about Mobius Digital's Outer Wilds and how it gets players implementing the scientific method. What I didn't discuss as much were the physical discoveries that the game incorporates into its universe. Scientists get accused of being closed-minded because they exclude the supernatural from their worldview, but this caricature of the profession is at odds with its history. Physics is full of concepts weirder than fiction, and its researchers have often overturned their long-held claims about the universe because new information came to light. Many of their peculiar discoveries are exhibited in the museum of Outer Wilds. The game borrows some phenomena from cosmology: the study of the magnificently large, and others from quantum physics: the science of the unfathomably small. In this article, we're going to look at both.

Black Holes

The curious Outer Wilds player will be no stranger to the black hole. For example, they'll have found the Nomai-engineered black hole in the centre of the planet Brittle Hollow and the one in the Ash Twin Project: the database of Nomai memories. The real-world conception of black holes began with the general theory of relativity, introduced by Einstein in 1915. General relativity forms the basis for our current understanding of gravity and came with a collection of "field equations": equations that can describe the folding of the fabric of our universe and the resultant gravity that folding creates. The first person to produce a solution for these equations was the German physicist Karl Schwarzschild, who made his publication soon after Einstein's.^[1]

The Schwarzschild Solution described a singular point in space with astronomically high density.^[2] The gravitational pull an object exerts depends on that density; the more matter in one spot, the stronger the gravity. A black hole is a lot of mass in one location, so its gravitational force would be so potent that it would drag in even the light around it.^[3] With no light emanating from the black hole, you couldn't see it, which is why it would be a "black" hole.^[2]

That hypothetical vortex was far-fetched enough that it was first thought to be a quirk of the mathematics; a concept that existed on paper but not in reality. Yet slowly, the scientific community came to see black holes' existence as a physical possibility.^[1] Then, in 1964, they found one: Cygnus X-1; they just couldn't confirm it was a black hole yet. It took the most esteemed physicists almost three decades to agree that Cygnus X-1 was the unicorn they'd been chasing. Today, estimates for the number of black holes in our galaxy start at an eye-watering ten million.^[3]

Outer Wilds simulates the pull of the black hole. Like the real deal, the game's gravity wells have an "event horizon": a definite point of no return for anything that falls in.^[2] In the game, the force of the singularity is tempered, perhaps a result of the Nomai being able to put a leash on it so that it doesn't tear apart their structures or bodies. The gravity of a real black hole can stretch any object or being into thin strings of matter in a process that physicists call "spaghettification". Really. In Outer Wilds, we can also see the true-to-life effect of light bending around black holes. The premise of using these objects to power technology may further have some grounding in solid physics.

Black holes emit a kind of radiation called "Hawking radiation". As radiation is just energy moving through space, that makes black holes a potential energy source. Other ideas for black hole power stations involve sapping energy from particle disintegration in them or leeching off of the fast-moving plasma orbiting them. Although, I can't stress enough that we're a long way from being able to implement any of these inventions.

The Schwarzchild black hole has another surprise that's also depicted in Outer Wilds. Any object or event that you can use Einstein's field equations to describe moving forwards in time, you can also calculate to be running backwards.^[2] So, what if we run the maths of the black hole in reverse? We get a white hole; a mathematical discovery first made by Austrian physicist Ludwig Flamm.^[4] Where no light can escape the black hole, and nothing will return from past its event horizon, light only exits the white hole, and nothing can enter its event horizon.^[2] In 1935, Albert Einstein and Nathan Rosen imagined white holes as the point of exit for anything that falls into black holes. They envisioned instances of the two objects connected by funnels that would later be called "Einstein-Rosen bridges" or "wormholes".^[4]

Einstein-Rosen bridges are the Nomais' universal expressway. You can see black and white holes contained in their teleporter entrances and exits, respectively. There's also an interface on the planet Ember Twin that lets you experiment with these passages. When you insert two warp cores into the machine, its interface resembles a Penrose diagram in the shape physicists use to describe the relationship between a white hole and black hole.^[2] Unfortunately, in the real world, we've never observed a wormhole or a white hole. Even on paper, there are enormous complications that would seem to prevent the possibility of a stable white hole or a wormhole you can traverse.^[4] Not least of which that white holes are posited as counterparts to black holes that have existed forever, and nothing in our universe has existed forever.^[2] In Outer Wilds' representation of them, it is engaging in speculation about what science could look like in the future rather than replicating a vision of the universe as we now understand it.

While the Nomai used wormholes to travel through time, they didn't leave an explanation of how they did it. Yet, some physicists have proposed that if you could move a wormhole exit at high speed relative to a wormhole entrance, that would allow you a shortcut through history.^[5] It's also worth noting that general relativity tells us that the closer you are to a black hole, the slower you move relative to people outside its influence. Because space and time are a single fabric, when the black hole drastically distorts space, it also distorts time. The gravity is stronger closer to the singularity, so the time distortion is too.

Meanwhile, special relativity shows that if you are moving faster than someone else through space, you also move faster than them through time. So, there are hypothetically ways we might use high-speed travel and enormous gravitational force to mess with the fourth dimension. We should, however, note that the temporal transportation we see in Outer Wilds is based on a totally speculative idea of how time works and that there's no current reason to believe wormholes are viable time machines, if they even exist.^[4][5]

Quantum Mechanics

From quantum mechanics, Outer Wilds takes the concept of superposition. The game's Quantum Moon can orbit any one of the six planets in its solar system but jumps between those planets when you're not observing it. Similarly, rocks that have broken off from this moon also teleport between a limited set of fixed locations when out of sight.

In opposition to classical physics, many measurements in quantum physics come with a heavy dose of uncertainty. For any property of a quantum particle, there are a number of different states we could find it in when we measure it. Prior to that measurement, we say that that property of the particle is in a "superposition" of each possible measurement; this means that various outcomes of measurement are possible, each with its own probability. So, before measurement, a photon could be in a superposition of lots of different velocities, but when we measure it, we find it moving at a specific velocity.

In Outer Wilds, we act like a physicist investigating a photon or other fundamental particle. We can narrow down a potential range of positions for the quantum rocks, but won't know exactly where they are until we check them. This effective teleportation of these stones becomes a hindrance to landing on the Quantum Moon. Its surface is shrouded by grey gas, which means that you cannot see most of the planetoid upon entering its atmosphere, giving it the chance to teleport out from under you. One way or another, you can eventually surmise that if you snap a photo of the moon with your scout and stare at it as you enter its atmosphere, you'll be able to continuously observe it as you land, keeping it in a single position.

The quantum rocks of Outer Wilds take these fuzzy effects that are so small as to be invisible and blow them up to a scale where we can see them and intuit their logic. I want to emphasise that some of the ways the Quantum Moon works are more interpretive than set in cold, hard facts. You could be forgiven for thinking that conscious observation affects quantum objects. This myth gets repeated all the time in popsci media, and some of the foremost minds in quantum mechanics, like Werner Heisenberg and John Wheeler believed it. Still, there's no experimental evidence to back up that claim. Additionally, there's no reason that looking at a photograph of something would affect the behaviour of the thing itself. An image of matter is not that matter.

Outer Wilds also has us play with a rule it calls quantum entanglement, but it has little to do with the actual phenomenon. In Outer Wilds, if you are touching a quantum object when it teleports, you teleport along with it. The game uses the term "entanglement" to refer to that coupling. In actual quantum mechanics, one particle can decay into two entangled particles. After this entanglement, you can measure a property of one of the particles and work out a certain statistical probability of finding the particle it is linked with in a certain and alternate state based on that measurement. For example, quantum particles have a property called "spin", and electrons can either be in a spin "up" state or a spin "down" state. So, if you entangle two electrons, and then you measure one and find it's spin "up", you know the other has a 100% chance of being spin "down" and vice-versa. As you can see, Outer Wilds borrows the name of this concept but not much else.

Supernovae

The black holes and quantum mechanics of Outer Wilds are often empowering to toy with, but there is a more apocalyptic and restrictive force at play in its solar system. At the end of every twenty-two-minute run, the star holding the system's planets in place goes supernova. Stars have a lot of mass compacted into a relatively tiny area. 99.8% of the matter in Earth's solar system is just the Sun. As was the case with black holes, a lot of mass in a tiny space means a hefty gravitational pull. So, the star is primed to collapse under its own gravity, but for most of its life, it doesn't.^[6]

Main sequences stars conduct nuclear fusion, literally the fusion of the nuclei of atoms. Fusion generates heat, and therefore, pressure. That pressure pushes outwards to the surface of the star, counteracting the gravity and preventing collapse. But eventually, the star burns through all its fuel and has nothing left to fuse. As fusion wanes, the heat reduces, which means the outward pressure lets up, and gravity wins out. A massive enough star in this state implodes, matter smashing into matter, generating an immense shockwave that can demolish entire planets.^[6] Although, I couldn't tell you whether the Outer Wilds star is large enough to undergo that catastrophic collapse.

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In most cases, I don't think criticising media as a 1:1 simulation of reality is helpful. That is not what media is. But art and entertainment do inevitably invoke and comment on some aspects of the universe we live in. As such, they have the potential to lead us towards certain conclusions, whether we're conscious of their pull on us or not, and I wouldn't want to mislead anyone by mindlessly parroting the observations of a game without any scepticism. I also think tangential learning can be a force for good, as long as we keep in mind that we are using the media as a jumping-off point to talk about another topic and not necessarily analysing the media itself. This earnest inquiry into the truth of the universe is the philosophy at the heart of Outer Wilds. Thanks for reading.

Sources

1. A Brief History of Black Holes by Sabine Hossenfelder (May 9, 2020), YouTube.
2. White Holes by PBS Space Time (August 30, 2017), YouTube.
3. Black Holes by NASA Staff (2010), NASA.
4. What is wormhole theory? by Nola Taylor Tillman and Ailsa Harvey (January 13, 2022), Space.com.
5. Is Time Travel Impossible? by PBS Space Time (October 21, 2019), YouTube.
6. What is a Supernova? by NASA Staff (July 23, 2021), NASA SpacePlace.

All other sources are linked at relevant points in the article.