Qubits & Zombies: Meet the Scientist Behind the World’s First Video Game for Quantum Computers
James Wootton used to be just a gamer first; then — a programmer. But that wasn’t enough. He decided to throw quantum computing into the mix.
The day eight-year-old James Wootton won a Game Boy after submitting his idea for a new Slush Puppy flavor, which was part of a competition in a wrestling magazine, his life changed. From that moment on in 1992 he became a gamer.
Fast-forward two decades — now Wootton is a big, beardy 35-year-old with a full head of messy hair, kind eyes and a shy smile. He is a gamer all right and does fit the bill perfectly — one could easily imagine him holed up in the basement (or the attic), in a hoodie and with headphones glued to his ears, for hours on end.
But here’s the thing: Wootton has also “always wanted to be a mad scientist,” he chuckles. So he became an IBM Research quantum physicist.
Back in his teens though his dream was to be a game designer. He would send his ideas to Nintendo, but “they would always respond with a pat on the head and a few badges,” he says. Stubbornly, he learned game design on his own. At IBM, he has finally been able not only to combine game design and gaming — but also throw physics into the mix.
An expert in all three fields, Wootton creates entertainment of the future. He’s the first person in the world to create a video game on a quantum computer.
Quantum computers hold great promises for anything from assessing risk in future investments to developing new drugs and novel materials much better than classical computers ever could. Unfortunately, they are not here yet, and it may take years before these fancy machines that look more like a golden chandelier have an advantage over your typical laptop, desktop or even a supercomputer.
The exception is gaming, to an extent. Because thanks to programmers like Wootton, it’s already happening. As we stand in the THINKLab at IBM Research lab in Zurich, with a quantum computer hanging an armlength away, Wootton shows me a game on his laptop that is similar to Minecraft. Dubbed Qiskit Blocks, this three-dimensional virtual landscape was partly built on a quantum computer.
QiskitBlocks is a game powered by Qiskit (qiskit.org) and Minetest (minetest.net) for teaching quantum computing to kids of all ages.
You’ve got this quantum garden, and puzzles in the garden as well as escape rooms to make it a bit more engaging,” says Wootton. The game, created by Wootton’s IBM colleague Jim Weaver, combines a range of different experiences to help people get to grips with what quantum programs look like, and what they could be used for. But the game is not just about quantum computers: one corner of the world contains an island that was actually created by IBM’s 53 qubit prototype device. The technique was developed by Wootton as a first example of how quantum computers can generate content for games. “The heart of it is image manipulation: a way of taking a simple bitmap image, encoding it as a quantum state and then using basic quantum operations to create something new.”
He’s the first person in the world to create a video game on a quantum computer.
Quantum computers rely on the weird properties of the small that we can’t observe in our daily life. Granted, at times people claim to feel certain connection when they are apart — especially, say, twins. Zoom in to get to the scale of atoms though — and you’ve got particles that can be entangled, meaning when one changes its state, the other one does too, simultaneously, even if they are light years apart.
Entanglement is just one of the properties of quantum mechanics; there’s also superposition, when a particle can be in multiple states at once, and interference. And that’s key for a quantum computer to work and to be, one day, much faster in computations than a standard computer.
A traditional computer depends on bits to run, and they can be at a specific state at any given time — either one, when the gate electric current is rushing through is open(‘on’) or zero, when it’s closed (‘off’). But at the heart of a quantum machine are qubits — atoms — that obey the rules of quantum mechanics and hence can be both one and zero at the same time. And the more qubits there are, the more combinations of zeros and ones the computer will work with, greatly speeding up its computational time.
For quantum mechanics, just like for Wootton and quantum gaming, it all started in a picturesque Alpine resort village in Switzerland — Arosa, a couple of hours drive from Zurich. That’s where in 1925 Erwin Schrodinger came up with his famous Schrodinger’s Equation while on vacation. The equation propelled the nascent field of quantum physics forward, allowing to solve for the so-called wave function of a particle, defining it completely — its position, its spin, and so on.
Arosa was where Wootton attended a conference, in early and very snowy January 2015. At IBM, his work has always been about decoding algorithms for quantum error correction — meaning dealing with the errors qubits are easily susceptible to. Qubits are fragile, and in today’s prototype quantum computers can only stay in superposition for milliseconds — not enough to perform useful computations just yet. To make them stay in the quantum realm for longer, researchers first try to suppress any external disturbances, or noise — from temperature fluctuations to physical vibrations and sound waves. Once the noise is low enough, researchers — including Wootton — try to correct any remaining errors using standard computers.
In Arosa, instead of enjoying the nearby ski slopes, Wootton had a chat with his fellow researchers from the Quantum Science and Technology (QSIT) center. One topic of conversation was a recent remark from the Swiss government, with poiliticians wondering when there would be more tangible quantum computing results actually useful to the population.
At first, Wootton was stumped — but then he “suddenly realized that my research was basically about solving puzzles,” he says. “So if I were to make those puzzles into a game, then I could make a citizen science project out of it” — to raise public awareness about quantum computing.
This was shortly before he joined IBM — and he asked his boss at the University of Basel to support him creating an educational game on a quantum computer and got an approval. He then asked QSIT for funding and received it. In 2016, Wootton made his first quantum game: Decodoku.
However, it was still a game about quantum computing, and it wasn’t the first. In fact it wasn’t even the first game-based quantum citizen science project: that honor belongs to Quantum Moves, a game created slightly earlier in 2016 by the Science at Home group of researchers at Aarhus University in Denmark.
That same year, though, IBM started the IBM Quantum Experience — an online platform that gives anyone in the world the possibility to use an IBM quantum computer via the cloud. And just like that, it became possible to make a game that actually used a quantum computer.
Wootton did just that. Using a software package known as Project Q, which provided a programmatic interface to the IBM Quantum Experience, he created his first truly quantum game in March 2017. It was a very simple example, conceived of and made in a single evening, based on the well-known Rock-Paper-Scissorsgame; Wootton called it Cat-Box-Scissors. It was a simple random number generator — but it was the first game ever created on a quantum computer.
Shortly after, he designed another game on the quantum machine, Battleships. This used the same method that many subsequent quantum games have done: take an existing game and implement it with a quantum twist. It takes the idea of Bell’s inequalities, which allowed us to prove that nature really does follow the unique rules of quantum mechanics and turns it into a way of keeping track of damage.
Wootton continued making games, following with Quantum Solitaire, a text-based dungeon crawler based on 1973’s Hunt the Wumpus and dubbed, rather appropriately, Hunt the Quantpus. When IBM put out Qiskit in March 2017, Wotton knew that it was much better software than Project Q for game design and “shifted loyalties very quickly,” he says.
Later, Wootton started to motivate other programmers to use IBM’s quantum machinery to design games via the cloud, and the peculiar fan base of quantum game developers started to grow. In 2019, he teamed up with the Quantum Game Jam — a Helsinki-based event that got together a crowd of game developers and quantum physicists to create games on a five and 16-qubit IBM quantum computer. They did it while sitting on a Ferris wheel, the Helsinki Skywheel, in sub-zero February temperatures and then enjoying the city’s most popular sauna with an open-air swimming pool, the Sea Allas Pool.
While today’s quantum games are still worlds apart from Rocket League, Overwatch or even Tetris, and resemble much more the games made on Atari 2600, Wootton is certain that very soon, they’ll become much more sophisticated.
But how is the actual programming different? How do you do it on a quantum computer that looks like a chandelier?
“The main difference is the level of abstraction,” says Wootton. “For normal programming, something like adding two numbers seems like the easiest thing you can do. But those numbers are encoded in a lot of bits, and the addition requires a lot of bitwise operations to be performed between the two numbers.” That’s something that we hardly think about when programming because we don’t really think about how our programs will look when compiled down to the bit level.
For quantum programming, however, Wootton needs to think about the qubits and to choose — typically — those that are less noisy. But sometimes, the noise is okay, he says — “if you find some way to make it okay.” For example, in his game Quantum Awesomness he ran a program and then measured the probability of getting a 1 output for each qubit. The program was designed so that the qubits could be paired up, with the two in each pair having the same probability as each other but different probabilities from the other pairs. The player was just given the probabilities and asked to find the pairs.
“Without noise, this would be trivially easy. With a little noise, it becomes challenging because the probabilities are not exactly as they should be. With a lot of noise, it becomes impossible,” laughs Wootton.
Another issue to bear in mind while programming on a quantum computer is uncertainty, a key feature in quantum programs. For normal digital computers, the output is a simple bit string. “That can be true for quantum computers too, but that bit string might be generated somewhat randomly. Which we might want to use, or to avoid,” says Wootton.
In his games, he typically tries to avoid the randomness coming into the game. For that, he usually samples many times to get probabilities, and then uses them as the variables in the game. For the Battleship successor game called Battleships with partial NOT gates, the probability of a 0 or 1 for a qubit represented how damaged a ship was. Noise became the central theme of the game, it’s what made it challenging — noise led to virtual weather features such as a sudden big wave rocking the ships. And by playing the game on different devices, players could get an idea of how noisy they were.
When quantum computers finally reach quantum advantage — meaning they’ll be able to perform at least one useful task better than a traditional computer — quantum gaming will take a leap forward, too. “There will be many things that will become possible in this era, and game developers will always find a way to use them,” says Wootton. While today, quantum games are mostly about solving puzzles, the next few decades should see gamers in hoodies tied to their quantum machines playing next-gen Red Dead Redemption and Fortnite — designed on a quantum computer.
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