- The Hollywood blockbuster "The Matrix" celebrated its 20th anniversary in March.
- The movie centers around the philosophical concept that our reality may not be real. The film's protagonist discovers that his world is a vast simulation run by hyper-intelligent AI.
- Since "The Matrix" came out, many scientists and philosophers have discussed the validity of the movie's claims.
- Nick Bostrum — an Oxford philosopher whose ideas have been echoed by Elon Musk — has argued that more likely than not, everyone on Earth today is living in a simulation.
When the film "The Matrix" came out 20 years ago (yes, it premiered in March 1999), many moviegoers pegged its premise as entertaining but fully implausible.
The movie's protagonist, Neo, discovers that his reality isn't actually real. Instead, Neo's world is a vast simulation orchestrated by hyper-evolved AI that harvest humans for their energy.
While this vision of robot overlords probably strikes most people as a stretch, the idea that we're living in a simulation is totally plausible, according to some philosophers, and maybe even likely.
Though Neo's bullet-dodging, gravity-defying antics may now seem dated to movie-goers, the concepts put forward in "The Matrix" remain perennial. Here's why some scientists think we're living in a simulation.
The odds of us living in reality are a billion to one, some say
In 2001, Nick Bostrom, a philosopher at the University of Oxford, circulated the first draft of a paper suggesting that a highly advanced supercomputer — with a mass on the order of a planet — would be capable of running a simulation on a humanity-size scale. ( Bostrum told Vulture that he hadn't seen "The Matrix" before publishing the paper.)
Bostrom said this computer would be capable of doing 10 42 calculations per second, and it could simulate the entire history of humankind (including all our thoughts, feelings, and memories) by using less than one-millionth of its processing power for just one second.
By this logic, all of humanity and our entire physical universe are just blips of data stored in the hard drive of a massive supercomputer.
He concluded: "We are almost certainly characters living in a computer simulation."
About 15 years later, Elon Musk — the founder of Tesla and SpaceX — echoed Bostrum's ideas. Musk said at a 2016 Recode conference that he thinks "the odds that we're in base reality is one in billions."
Today, Bostrum is still thinking and talking about the fraught relationship between humans and computers — in a speech at this year's TED conference, he put forward the frightening idea that humanity could destroy itself with a technology of our own creation.
Bostrom went on to suggest that the way to save us from ourselves is simple: mass surveillance using AI.
One scientist argues that our reality is akin to a giant multiplayer video game
Rizwan Virk, a computer scientist and the author of the new book "The Simulation Hypothesis," told Vox that he also thinks "there's a very good chance we are, in fact, living in a simulation."
Virk imagines this as "the video game of life," which he calls "the Great Simulation."
"You can think of it like a high resolution or high-fidelity video game in which we are all characters," he told Vox.
Virk, who is also a video game designer, said the simulated video game-like universe that we might be living in — which is indistinguishable from reality for us — is far more sophisticated than the giant multiplayer online games that humans currently create, like World of Warcraft and Fortnite.
He acknowledged, of course, that nobody can me 100% confident that we're living in a simulation, but said "there is plenty of evidence that points in that direction."
Some researchers are trying to test Bostrum's theory
Since Bostrum's paper came out, academics have been trying to test the idea that humanity is living in a simulation.
In 2017, a study in the journal Science Advances argued that one type of limited simulation couldn't work due to hardware issues. Essentially, the study authors said that classical computers don't have enough memory to simulate certain scenarios in our lives and store the information.
A group of physicists also tried to address these questions by studying cosmic rays. Physicists simulate space, and the subatomic particles in it, using coordinates on a grid. So nuclear physicist Silas Beane and some colleagues suggested in a 2014 paper that perhaps the mass simulation we could be living in would use that same coordinate system. Their logic was that if certain particles — like high-energy cosmic rays — always exhibit a maximum energy level (which, it turns out, they do), then the constraints on their behavior could be due to the simulation's underlying grid.
"There always remains the possibility for the simulated to discover the simulators," the authors said in the paper.
But we may never know the answer
Many scientists argue, however, that we'll never be able to figure out whether or not we're living in a simulation.
Marcelo Gleiser, a physicist and philosopher at Dartmouth College, told New Scientist that trying to address Bostrum's question based on our current knowledge and technological capabilities is pretty hopeless. That's because if we were really living in a simulation, scientists wouldn't have any idea about the laws of physics in the "real world" outside. They also wouldn't know what kinds of computations would be possible outside the bounds of our simulation, Gleiser said.
So everything that we think we know about what's possible in terms of computing power or the laws of physics could just be another aspect of the simulation.
Beane has expressed similar skepticism.
"If we're indeed a simulation, then that would be a logical possibility, that what we're measuring aren't really the laws of nature, they're some sort of attempt at some sort of artificial law that the simulators have come up with," he told Discover Magazine.
Bostrum, however, remains convinced of his theory that we are most likely in a simulation.
"At the meta level, I haven't really seen any convincing objections or attempts at refutation," he told Vulture. "So the absence of that also, I guess, strengthens my confidence that the reasoning is sound."