The question of whether reality is in fact “real” has plagued philosophers since the days of Plato, but in these technology-driven times, in which concepts like virtual reality seem more and more plausible each year, the eternal question of “is any of this real?” has been altered to include the addendum “are we  all just living in a computer?” While you may be quick to brush the idea off as the sophist ramblings often heard from the creators of The Matrix, in 2003,  Oxford University Professor of Philosophy Nick Bostrom decided to take the question far more seriously, and he has come to some rather startling results: not only is entirely possible that we are living inside an incomprehensibly complex computer program, but it is almost a certainty.

While it may sound far-fetched, Bostrom’s explanation in his 2003 paper can be boiled down to a few unavoidable truths, namely the inevitability of computer technology eventually reaching a point in which our descendants would be capable of creating planet-sized computers that can run what he refers to as “ancestor simulations.”

“Just as we can build simple virtual realities today with simple simulated creatures living inside them, maybe in the future with vastly more powerful computers you can build more complex virtual realities with more complex simulated creatures inside them,” said Bostrom at the World Science Festival. “Maybe these creatures can be complex enough that they would actually have brains like ours to make it down to the level of individual neurons and synapses  such that the inhabitants of these simulations would be conscious.”

From there, Bostrom goes on to explain that once it is understood that this level of strength in computing power would eventually be attainable, that then that his simulation argument imposes a constraint on what must be accepted as true. According to Bostrom, one of the following options must be true:

  • The human species is very likely to go extinct before reaching a “posthuman” stage.
  • Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof).
  • We are almost certainly living in a computer simulation.

According to Bostrom, the reason why discarding the first two possibilities would inevitably indicate that we are “almost certainly” living in a computer has everything to do with odds. By accepting that some fraction of current human civilization survives to this level of technological maturity, and if this civilization has both the interest and resources to run these simulations, then the number of simulated histories will vastly outnumber actual courses of history. Meaning that statistically speaking, the chances that this is the real version of history becomes far less likely than possibility that this is a simulation.

“If you calculate the computing power  that a technologically mature civilization would have, and the computing power that would required to simulate all human brains, it turns out that the latter quantities is a tiny, tiny fraction of the former,” said Bostrom. “So, in other words, by devoting a tiny fraction of their computational resources at their end, they would be capable of creating billions and billions of simulations.”

While initially difficult to grasp, Bostrom’s theory does make quite a bit of sense, if not lacking in empirical evidence. But now, almost ten years after Bostrom put this theory forward, some phycists believe that we will soon be able to test whether or not we are all simply highly-complex lines of code.

Martin Savage, professor of physics at the University of Washington, believe that scientists should be able to conduct tests capable of  detecting the constraints inherent in these simulations by limited resources. In a technique known as “lattice quantum chromodynamics” that simply factors in the fundamental laws of physics, supercomputers are currently able to simulate a small portion of the universe, scaled at one 100-trillionth of a meter, or roughly the size of the nucleus of an atom.

This lattice  is used to model the space-time continuum on a four-dimensional grid, and allows phycists to examine the interaction of the various forces binding the universe together. Savage believes that signatures of resource constraint similar to what is found in current simulations would likely exist in future simulations as well, and that would include the impression of a lattice similar to what is used today.

“If you make the simulations big enough, something like our universe should emerge,” Savage said.

As the UW resarch team explains in a research paper, this signature would likely present itself as a limitation the energy of cosmic rays. In a simulation, it would be likely to see the cosmic rays with the highest amount of energy would travel diagonally across the lattice, instead of equally moving in all directions. As far as we’re currently capable of imagining, this would be the first testable way of determing whether we are living in a computer simulation.

For a more comprehensive explanation on the simulation theory, here is a video of Bostrom taken from the World Science Festival.