With your support we can make our show better! Join our Patreon community: http://bit.ly/whatif-patreon If time travel is possible, why haven't we met a single time traveler yet? And if we did meet one, how would we know they weren't faking it? What would their time machine look like? And how would it operate? Would there be a set of rules for time travelers to follow? And what would happen if they decided to break them? Transcript and sources: https://insh.world/science/what-if-you-met-a-time-traveler/ Music: http://bit.ly/whatif-music Watch more what-if scenarios: Planet Earth: https://www.youtube.com/watch?v=_-HhCwYD7rc&list=PLZdXRHYAVxTJCzxwmCq0NNpYq9N9wyb2l The Cosmos: https://www.youtube.com/watch?v=gfuJyVkMH_g&list=PLZdXRHYAVxTJno6oFF9nLGuwXNGYHmE8U Technology: https://www.youtube.com/watch?v=CS3bBO05fpU&list=PLZdXRHYAVxTIeRY3JtgXgoGqSEB7kDdKO Your Body: https://www.youtube.com/watch?v=QmXR46TrbA8&list=PLZdXRHYAVxTJNsV9FFeNAKl2ySsHj8GZO Humanity: https://www.youtube.com/watch?v=fdCDQIyXGnw&list=PLZdXRHYAVxTIFnvmOeWbv-Mt8zFxSCSvZ What If elsewhere: IG: https://www.instagram.com/whatif.show/ Twitter: https://twitter.com/WhatIfScience Facebook: https://www.facebook.com/What.If.science Suggest an episode: http://bit.ly/suggest-whatif T-shirts and merch: http://bit.ly/whatifshop "Imagination will often carry us to worlds that never were. But without it, we go nowhere." — Carl Sagan What If is a mini-documentary web series that takes you on an epic journey through hypothetical worlds and possibilities. Join us on an imaginary adventure — grounded in scientific theory — through time, space and chance, as we ask what if some of the most fundamental aspects of our existence were different. Feedback, inquiries and suggestions: https://underknown.com/contact