"What if dinosaurs still ruled the Earth, the Russians got to the moon first, everyone became vegetarian or time itself flowed backwards? And that's just for starters ... What if the laws of physics were different? What if our machines become smarter than us? Or, if every human vanished tomorrow? The answers to these questions aren't just fun to consider, but reveal deep truths about our own existence. Join New Scientist on a thrilling journey through dozens of incredible but perfectly possible alternative realities - and rediscover your place in the universe"--