“Traveling through time is the weirdest feeling. When you go very fast through space – by car or speedboat, say, or if you’ve ever ridden a motorcycle – it feels urgent. Everything moves. The world whips past you, trees and houses or bouys and boats, the wind in your hair, here vanishing away, there looming up to meet you, then rushing by.

When you travel through time, you get the same headlong urgency but minus the here and there. The result is a horrible, unsettling feeling of motion in stillness. You hurtle without moving. Every second you feel you’re about to crash into the unknown.

It’s even worse when you’re going backwards, into the past instead of the future. Not only are you hurtling blindly at unnatural speed (if speed is even the word for it), but your body somehow knows that you’re going in the wrong direction. Time closes over your head. It’s like drowning.”

“We poured through time again with the same headlong, motionless hurtling, but this time it was different – maybe because we were going in the right direction. I felt like I was winning a game, acing a test. An upside-down waterfall of hope cascaded through me, starting in the soles of my feet and babbling out through my head.”