Imagine time running backwards. People would grow younger instead of older and, after a long life of gradual rejuvenation – unlearning everything they know – they would end as a twinkle in their parents' eyes. That’s time as represented in a novel by science fiction writer Philip K Dick but, surprisingly, time’s direction is also an issue that cosmologists are grappling with.
You may have heard that Apple and the FBI are fighting over an iPhone recovered during the investigation of the San Bernardino massacre last December, and that it may have serious implications for your own smartphone.
True innovation is hard to find, as few things come out of nothing. Take the now ubiquitous selfie, for example. The format may have changed but the concept of making self-portraits is hundreds, if not thousands of years old. The same is true of many inventions that we typically think of as modern, some of which actually have precedents dating back over 1000 years.