What is time? One of the earliest concepts proposed is that is simply the fourth dimension, another direction.

Humans travel daily one way into the future. Science fiction writers have long been obsessed with the subject from the legendary “The Time Machine”
by HG Wells to the the Doctor Who series about the last time lord and his adventures. From summer blockbusters to sensational science headlines, modern culture is constantly inundated with tales of time travel. But when you boil down the physics involved, is it possible to travel through time?