The ABC of Time
Matt Farr: There are many different ways in which time might be thought to ‘have a direction’ but, to keep things simple, let’s work with the following idea: if time has a direction, then presumably it could have had the opposite direction; a universe just like this one but with the opposite direction of time would constitute a different universe to our own. Perhaps it is even possible that, contrary to our beliefs, our world actually runs from future to past. Such a backwards-in-time world, replete with its unlikely and unfamiliar processes, would surely be fundamentally unlike the one in which we think we live, and so our ordinary beliefs about time would be wildly mistaken. This is exactly what my preferred theory of time — what I call the ‘C-theory’ — rejects. According to the C-theory of time, it is not possible for this Universe to have run in the opposite direction of time, for there is no such thing as ‘the direction of time’ that could be reversed. This is the theory of time that I think fits best with our scientific understanding of the world.