Scientists and philosophers have argued over the nature of time since … well, since time immemorial.
Does time flow unceasingly in one direction? Is our perception of time merely an illusion? Does each instant exist eternally, and are we just running through a sequence of instants like film in a movie projector? And if that’s the case, can we run the film backward? Could we even change what happens in the movie?
In a new book called “On Time” — and in the latest episode of the Fiction Science podcast — British physicist Jim Al-Khalili lays out what he thinks is the answer to such questions.
What’s his answer? Spoilers ahead …