The Portal Paradox

From Minute Physics.

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This video is about the Portal Paradox – a paradox in the video game Portal (and Portal 2) regarding whether or not a companion cube passing through a moving portal plops out of the other end with no speed (velocity, momentum), or shoots out at high speed. It’s a question of conservation of momentum, relativity of velocities, wormholes, 3D printers and quantum teleportation, glitches, and more.


Conservation of momentum

Principle of Locality

YouTube video of testing the Portal 2 game engine on the portal Paradox

Tutorial for how to program the Portal portals on your own:

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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