There have been fake Iraqi villages in the American desert since 2007. They’re like tricycles for American troops, to help them circle the parking lot a few times before ditching the training wheels and wobbling off down the war-path. In Hari Kunzru’s Gods Without Men, Laila, a teenager who has recently immigrated to America from Iraq, is hired to live in Wadi al-Hamam, one of these simulated villages. She plays the role of “Rafah,” a village woman who hates the Americans for killing her father:
Wadi al-Hamam was weird. The village looked exactly like one of the little towns where her mother had family….When violence was on the menu the villagers had to wear special harnesses over their traditional ethnic clothing, so the laser-guns could register hits…There were scorekeepers who tallied up the net effect on the hearts and minds of Wadi al-Hamam, and, depending on how things had gone, they would be told in the next day’s briefing whether they felt more or less pro-American.
The houses are shipping containers with false fronts, and the imam is a hairdresser who lovingly crafted his impressive beard by hand. Wadi al-Hamam isn’t real, and everyone there knows it.
But what about us? A joint team of American and German physicists—Silas R. Beane, Zohreh Davoudi, and Martin J. Savage—published a paper in November of 2012 arguing that it may be possible to prove that we too are living in a simulated world.
The argument—well, the argument is complicated. If the phrase, “At fixed quark masses, the CRR of a lattice ensemble generation (in units of petaFLOP-years) scales roughly as the dimensionless number λQCDL5/b6, where λQCD ≡ 1 fm is a typical QCD distance scale,” means something to you, by all means read Beane et al’s paper here: If “petaFLOP” sounds to you like a failed animal-rights protest, allow me to make a stab at an explanation:
Essentially, physicists are already capable of simulating tiny, tiny parts of our universe. They make the simulations on a computer, built on structures called lattices. To wrap their simulations around these lattices, they have to put limits on certain physical laws. And, as it turns out, the universe we live in has some limits that look suspiciously similar. The Greisen-Zatsepin-Kuzmin, or GZK cutoff, is a limit on the energy of cosmic rays that would, the researchers say, be consistent with a universe built on a lattice. In fact, it might be possible to reveal such a lattice by measuring how these rays travel. This is something we could do with current knowledge and technology.
While it’s new to propose a concrete method for proving it, the idea that our universe may be a computer simulation has been kicking around for a while. In 2003, Oxford philosophy professor Nick Bostrom published a paper using propositional logic to assess the likelihood that we are living in a meticulous reconstruction of the past put together by our own descendants. In this theory, we’re a sort of unwitting Upper Canada Village where our exponentially great grandkids bring their toddlers to gawk at the spandex work-out clothes and primitive iPads. Basically, because we can already make very small simulations, it is reasonable to assume that we will figure out how to make bigger and better ones until we manage to simulate our entire universe. And once we’ve done it once, we’ll probably do it again. From there, it’s a simple probability problem: all it takes is one “real” human race to make more than one “fake” human races for the simulations to outnumber the real. If there are two fake universes for every real one, odds are that you and I live in one of the fake ones. And as the universes proliferate, Bostrom goes on to argue:
[O]ne can consider a sequence of possible situations in which an increasing fraction of all people live in simulations: 98%, 99%, 99.9%, 99.9999%, and so on. As one approaches the limiting case in which everybody is in a simulation (from which one can deductively infer that one is in a simulation oneself), it is plausible to require that the credence one assigns to being in a simulation gradually approach the limiting case of complete certainty[.]
I can’t quite decide whether I mind being a simulation or not. I’m a different type of nerd from the nerds who genuinely understand what quark masses are. I’m an arts nerd, and to me living in a computer simulation sounds a lot like living in a novel. Is Elizabeth Bennet not a real person? Her world is limited by the laws of fiction—story, character development, conflict—and is a kind of recreation of Austen’s world. Yet Elizabeth Bennet is more enduring—and probably better loved—than any nineteenth-century smart-aleck made of flesh and blood. The striking feature of something that’s been deliberately brought into being is that someone, somewhere, decided it was worth having around.
The question of whether it matters whether we’re a simulation depends on what the simulation is for. If I’m a false version of reality, I would rather be some 31st-century genius’s art project than some 42nd-century hack’s fudged budget for the Intergalactic Arts Council. I’d rather be a cog in an experiment designed to breed a fluffier rabbit than a cog in an experiment designed to come up with a popsicle that can be served warm. (Actually, I’d be okay with that being the whole point of our universe.)
I once visited a warehouse basement where a group of men in their 60s worked every Wednesday on a model railroad that had been continuously added onto since the 1930s. I watched one man add grass to a hillside; he was using individual strips of material in several shades of green. He had short lengths for the manicured lawn near the footpath, and longer ones for the marshy, untamed lushness climbing up the embankment. I like to think of our universe bathed in that attention, lavished with many shades of green.