Despite how it may feel some days, we probably aren’t stuck in a computer simulation. An international team of mathematicians says that they have once-and-for-all determined that our reality is, in fact, real. According to some of the latest mindbending quantum theories combined with centuries’ old mathematical theorems, their study published in the Journal of Holography Applications in Physics states the popular simulation theory is more than improbable—it’s fundamentally impossible.
What is the ‘Simulation Hypothesis?’
The possibility that our entire universe merely exists inside a computer simulation is more than an idle science fiction thought experiment. Physicists, mathematicians, philosophers, and college dorm roommates have argued over the scenario’s feasibility since the dawn of the digital age in the 20th century.
However, the debate about whether or not any of this is “real” stretches thousands of years into the past. Indian mystics, ancient Greek thinkers, Chinese theorists, and Aztec priests all put forth various takes on the validity of what we see around us. These discussions get even more complicated when you add modern supercomputers into the situation.
“If such a simulation were possible, the simulated universe could itself give rise to life, which in turn might create its own simulation,” University of British Columbia quantum researcher Mir Faizal explained in a statement. “This recursive possibility makes it seem highly unlikely that our universe is the original one, rather than a simulation nested within another simulation.”
Although many experts initially believed that the concept was impossible to reliably explore using logical reasoning, Faizal and his colleagues believe their research shows, “it can, in fact, be scientifically addressed.”
But first, it’s probably best to prepare for some truly mindbending subject matter.
Quantum gravity and Gödelian guideposts
The extremely condensed history of physics goes like this: Newtonian physics rooted in his laws of motion, then Einstein’s theory of relativity, and finally quantum mechanics. This most recent era centers on a field called quantum gravity. As its name implies, quantum gravity seeks to unify the theories of gravity and quantum physics without ignoring either’s effects. So far, the results suggest that even space and time aren’t fundamental. Instead, they are rooted in a mathematical foundation of pure information that exists in a “Platonic realm.” This math dimension is what generates space and time, and is therefore more “real” than the physical universe as experienced by humans.
With all that in mind, Faizal’s team says that this foundation of mathematical information can’t describe reality solely through computation. The only way to generate a complete, reliable theory of everything necessitates a concept they call non-algorithmic understanding.
In order to get to a non-algorithmic understanding, Gödel’s incompleteness theorem must be integrated into the equation. Introduced by its namesake Kurt Gödel in 1931, the idea is deceptively simple at first glance–no collection of algorithms or axioms alone can indisputably prove every true fact about numbers or computation.
The study’s authors use this basic statement as an example of Gödel’s incompleteness theorem: “This true statement is not provable.”
If you could prove the statement, then it wouldn’t be “true.” If it’s not provable, then it’s technically true…and yet it would be impossible to show the evidence.
Regardless, computation falls apart in the face of Gödel’s theorem.
“Therefore, no physically complete and consistent theory of everything can be derived from computation alone,” argued Faizal. “Rather, it requires a non-algorithmic understanding, which is more fundamental than the computational laws of quantum gravity and therefore more fundamental than spacetime itself.”
If non-algorithmic understanding is beyond the capabilities of a computer, then even the most advanced supercomputer possible could never properly simulate reality.
“Any simulation is inherently algorithmic—it must follow programmed rules,” Faizal summarized. “But since the fundamental level of reality is based on non-algorithmic understanding, the universe cannot be, and could never be, a simulation.”
Study co-author Lawrence Krauss added that many researchers assumed they might one day describe a fundamental theory of everything through purely computational methods.
“We have demonstrated that this is not possible,” he said. “A complete and consistent description of reality requires something deeper.”
A possibly ‘profound logical fallacy’
As with most great debates, not everyone is convinced. University of Portsmouth physicist and the head of the Information Physics Institute Melvin Vopson has spent years investigating the possibilities of simulated reality. Most recently, Vopson proposed that gravity itself may prove we really are in a computer simulation. As it stands, Vopson is unmoved.
“While I have the greatest respect for any attempt to apply mathematical rigor to fundamental questions, the conclusion…appears to be the product of a profound logical fallacy,” he tells Popular Science.
Vopson cites the authors’ attempt to use the rules experienced in our perceived reality to, “set limits upon the system that hosts our reality.” He also believes that reality doesn’t need to be a simulation to still function as a cosmic computational process.
“It could mean that our universe is a giant computer that computes itself,” says Vopson.
Both Vopson and Information Physics Institute colleague Javier Moreno call Faizal’s argument “superficially compelling,” but guilty of a “profound category error” in the assumption that a simulation must run on computations existing in the simulation itself. For example, it doesn’t account for a simulation that operates on a higher order of physics or dimensionality unbound by the simulation’s internal laws. It could be that the underlying mechanics of our simulation aren’t limited by the speed of light or standard particle physics behavior.
“Any ‘mathematical proof’ derived from our physics [or] mathematics like those mentioned in the article is merely a calculation of the computational cost using our own rules,” Vopson and Moreno concluded.
As confident as Faizal’s team is in their own results, for now, the true reality of the simulation hypothesis may remain elusive—no pun intended.
