December 18, 2016
By Philip Ball
Are you real? What about me?
These used to be questions that only philosophers worried about. Scientists just got on with figuring out how the world is, and why. But some of the current best guesses about how the world is seem to leave the question hanging over science too.
Several physicists, cosmologists and technologists are now happy to entertain the idea that we are all living inside a gigantic computer simulation, experiencing a Matrix-style virtual world that we mistakenly think is real.
Our instincts rebel, of course. It all feels too real to be a simulation. The weight of the cup in my hand, the rich aroma of the coffee it contains, the sounds all around me – how can such richness of experience be faked?
But then consider the extraordinary progress in computer and information technologies over the past few decades. Computers have given us games of uncanny realism – with autonomous characters responding to our choices – as well as virtual-reality simulators of tremendous persuasive power.
It is enough to make you paranoid.
The Matrix formulated the narrative with unprecedented clarity. In that story, humans are locked by a malignant power into a virtual world that they accept unquestioningly as “real”. But the science-fiction nightmare of being trapped in a universe manufactured within our minds can be traced back further, for instance to David Cronenberg’s Videodrome (1983) and Terry Gilliam’s Brazil (1985).
Over all these dystopian visions, there loom two questions. How would we know? And would it matter anyway?
The idea that we live in a simulation has some high-profile advocates.
In June 2016, technology entrepreneur Elon Musk asserted that the odds are “a billion to one” against us living in “base reality”.
Similarly, Google’s machine-intelligence guru Ray Kurzweil has suggested that “maybe our whole universe is a science experiment of some junior high-school student in another universe”
What’s more, some physicists are willing to entertain the possibility. In April 2016, several of them debated the issue at the American Museum of Natural History in New York, US.
None of these people are proposing that we are physical beings held in some gloopy vat and wired up to believe in the world around us, as in The Matrix.
Instead, there are at least two other ways that the Universe around us might not be the real one.
Cosmologist Alan Guth of the Massachusetts Institute of Technology, US has suggested that our entire Universe might be real yet still a kind of lab experiment. The idea is that our Universe was created by some super-intelligence, much as biologists breed colonies of micro-organisms.