Reality check: could our universe be a simulation?

Are we all living in a computer simulation? Is the world we imagine to be real simply virtual reality instead, an elaborate computer program? That sounds ridiculous, but nonetheless it’s what many clever people actually think — or at least, think possible. One of them, the philosopher David Chalmers, has just written a book on the subject, Reality +: Virtual Worlds and the Problems of Philosophy.

Chalmers is a serious intellect. He won a bronze medal in the International Mathematical Olympiad as a child and did his undergraduate studies in Pure Mathematics before turning to philosophy.

Part of his argument is that we are already building simulated worlds ourselves — computer games as well as virtual environments like Second Life. These are becoming increasingly realistic. In time — Chalmers estimates about 100 years — they will be indistinguishable from the physical world and people will spend their lives in them. By then it will also be possible to create many different universes, and the population of these multiple simulations will far exceed that of the physical world.