‘There is no such thing as past or future’: physicist Carlo Rovelli on changing how we think about time

Seven Brief Lessons on Physics sold over a million copies around the world. Now Rovelli is back to explore the mysteries of time. He tells Charlotte Higgins about student revolution and how his quantum leap began with an acid trip

Extract from Carlo Rovelli’s new book: on the elastic concept of time

What do we know about time? Language tells us that it “passes”, it moves like a great river, inexorably dragging us with it, and, in the end, washes us up on its shore while it continues, unstoppable. Time flows. It moves ever forwards. Or does it? Poets also tell us that time stumbles or creeps or slows or even, at times, seems to stop. They tell us that the past might be inescapable, immanent in objects or people or landscapes. When Juliet is waiting for Romeo, time passes sluggishly: she longs for Phaethon to take the reins ...