What Would It Take to Build a Time Machine?

Imagine climbing into a machine that could whisk you back to ancient Rome or forward to a distant star. This book for middle-grade readers explains the scientific ideas from Einstein's relativity to black holes and wormholes that researchers think might one day power a real-life time machine. It also highlights the huge technical challenges and unanswered questions that scientists still face, inviting readers to think like physicists as they consider what it would truly take to turn time travel from fiction into fact.