Twenty years ago it was the plot of The Matrix, but experiments set to begin in the near future, pandemic permitting, in California hope to show that the world is, indeed, an illusion.

The idea that we are living in a simulation is viewed simply as science fiction by most mainstream scientists but it has some surprising and high-profile supporters, including Tesla and SpaceX entrepreneur Elon Musk, who has said the odds are "a billion to one" against us living in base reality, and analysts at Bank of America, who estimated its likelihood at between 20 and 50 per cent in a 2016 report.