• rog@lemmy.one
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      1 year ago

      Its just a hole though. If you have a tennis racket with no strings and swing it over something stationary the object doesnt move

      • silly goose meekah@lemmy.world
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        1 year ago

        With the tennis racket analogy both portals would be moving. In the thought experiment from the image just one is moving, resulting in an unaccounted for momentum, unless the people shoot out the blue portal