It’s almost as common to ponder the meaning of our existence as it is to question what the boundaries of said existence are, which leads to the kinds of discussions that usually occur post-drinking but pre-Taco Bell run. What is consciousness? If our light receptors don’t perceive colors in the exact same way, then was that really a “red” light we just ran? And the classic “could Jesus microwave a burrito so hot, that He himself could not eat it?”
These quandaries keep everyone from pop-culture writers to tech billionaires (who are only slightly more influential) up at night. After devoting much time and money to exploring artificial intelligence—including making robots pump iron so he could determine whether or not an exercise regimen would make them more dangerous—Elon Musk recently decided that there’s only a “one in a billion” chance that the reality we’re currently living in isn’t just a very sophisticated simulation. The Tesla founder doesn’t just share this belief with other very rich men who probably communicate via hologram; this “simulation hypothesis” has been around since well before The Matrix, plaguing previous generations of philosophy and physics students.
Musk and others who doubt that we live in base reality are working from a theory that, given humanity’s technological strides, it’s not only possible but pretty goddamn likely that there’s already some super-powerful computer that has created this simulation for us. You know, because we now have games like Horizon Zero Dawn just 40 or so years after Pong (look, that’s his thinking, not ours).
But Musk and his fellow tech giants can rest easy, as Cosmos Magazine reports that we are almost certainly not living in a computer simulation. The publication cites a paper by a team of theoretical physicists at Oxford University, published in the Science Advances journal if you want to go further down the rabbit hole, that has apparently found that no extraterrestrial computer could whip up our reality. The paper’s authors, Zohar Ringel and Dmitry Kovrizhi, have shown that “constructing a computer simulation of a particular quantum phenomenon that occurs in metals is impossible—not just practically, but in principle.”
As for just how they were able to demonstrate this, it was kind of a happy accident. Ringel and Kovrizhi were using quantum Monte Carlo simulations, which is a type of computation used to generate random numbers, to study something known as the quantum Hall effect (we’re just a little out of our depth now). The pair then “showed that attempts to use quantum Monte Carlo to model systems exhibiting anomalies, such as the quantum Hall effect, will always become unworkable,” and discovered that “the complexity of the simulation increased exponentially with the number of particles being simulated.” And here’s the kicker: if “complexity grows on an exponential scale—where the amount of computing power has to double every time a single particle is added—then the task quickly becomes impossible.” This storage problem came up fairly quickly, with Ringel and Kovrizhi calculating that “just storing information about a couple of hundred electrons would require a computer memory that would physically require more atoms than exist in the universe.” Basically, the kind of computer needed to create this simulation couldn’t exist.
There is a caveat, as “the researchers note that there are a number of other known quantum interactions for which predictive algorithms have not yet been found. They suggest that for some of these they may in fact never be found.” They’re also modeling this after classical or terrestrial computers, which could affect the limitations. But while there’s no way (currently) to prove definitively that we’re not in a simulation, the theory that’s keeping folks like Musk up at night doesn’t really hold water.