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For ages I’ve been thinking about doing a video analyzing time travel in fiction and doing a comparison of different fictional time travels – some do use wormholes, some relativistic/faster than light travel with time dilation, some closed timelike curves, some have essentially “magic” or no consistent rules that make any sense, or TARDIS's, or whatever. This video is an explanation of how time travel functions in different popular movies, books, & shows – not how it works “under the hood", but how it causally affects the perspective of characters’ timelines (who has free will? can you change things by going back to the past or forwards into the future?). In particular, I explain Ender's Game, Planet of the Apes, Harry Potter and the Prisoner of Azkaban, Primer, Bill & Ted’s Excellent Adventure, Back to the Future, Groundhog Day, Looper, the video game “Braid”, and Lifeline.

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Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute!

Created by Henry Reich