Thought experiment: quantum computers & replicating our reality
In this column, I’d like to share a thought experiment with you. It’s about quantum computers and simulating our reality.
Published on May 9, 2026
Our DATA+ expert and Editor-in-Chief, Elcke Vels, explores AI, cyber security, and Dutch innovation. Her "What if..." column imagines bold scenarios beyond the norm.
I was recently watching the series Devs, and after the very last episode, I found myself staring at the ceiling for far too long. In Devs, a tech company builds a gigantic quantum computer that can not only examine the past but also simulate the entire reality. Every movement of every particle. Every choice. Every person. The idea is simple: if the universe consists entirely of the laws of nature, then an extremely powerful computer should be able to predict reality exactly. Not approximately. Just completely.
Sounds like science fiction. (It is.) But at the same time, we’re already at the beginning of something that looks suspiciously like the first version of that.
Today’s quantum computers
Companies like IBM Quantum, Google Quantum AI, and IonQ are already building powerful quantum computers capable of performing calculations that we cannot do with normal computers. We can already put quantum computers to good use. And even more so in the near future. For chemistry, for example. Materials science. For creating personalized medicines. At some point, we may even be able to make highly accurate predictions about traffic conditions and the weather. But in theory, it could go much further. Much further.
Staring at the ceiling
And now, the reason I was staring at the ceiling. If a hyper-intelligent civilization can perfectly simulate an entire world—including people who feel conscious—what are the odds that we’re actually living in “real” reality? Why would we be the original version, exactly? The first layer? The real world at the bottom of the stack?
Once it becomes technically possible to create a single realistic simulation, millions might follow. Billions, even. Worlds within worlds within worlds. Statistically speaking, it then becomes almost strange to think that we happen to be in the original reality. That’s what I think, anyway.
Normally, I’m not at all susceptible to conspiracy theories, superstition, or woo-woo ideas. But this feels frustratingly logical in my head.
Okay. Maybe I’ve pushed you a little bit down the rabbit hole with this. Admittedly, I might have done that a little bit on purpose. Because honestly? Sparring partners are more than welcome.
In the meantime, I’m trying to get used to the idea that I’m typing this text in the 3,000th, simulated layer of reality.