A causal loop is a classic time travel conundrum. If you send information to the past – say, you give Albert Einstein the formula E=mc ² before he theorises it himself, then he publishes it and you go ...

From 12 minutes to Deathloop to Outer Wilds, time loop games are having a real moment right now. And that’s not even mentioning all the TV shows and movies dipping their toe into the time stream. Part ...

When Seth Lloyd first published his ideas about quantum time loops, he hadn’t considered all the consequences. For one thing, he hadn’t anticipated the countless emails he would get from would-be time ...