Google, it has emerged, has built a 'Matrix-style' simulation of the entirety of California to test its self-driving cars. While this in itself isn't massively surprising given Google's history as a software company (though it is a bit scary), the company is also petitioning California's state officials to allow safety testing within the Matrix, instead of testing on real roads. This might sound a little terrifying, but it makes quite a lot of sense for a self-driving car, where there are millions of conditions that need to be tested.