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Einstein's twin paradox explained - Amber Stuver


2,260 Questions Answered

TEDEd Animation

Let’s Begin…

On their 20th birthday, identical twin astronauts volunteer for an experiment. Terra will remain on Earth, while Stella will board a spaceship. Stella’s ship will travel to visit a star that is 10 light-years away, then return to Earth. As they prepare to part ways, the twins wonder what will happen when they’re reunited. Who will be older? Amber Stuver investigates the “Twin Paradox.”

If Stella measures Terra’s time passing slower than her own, Terra will see Stella’s time passing faster than her own. Stella will always measure her time passing at the same rate regardless of how fast she is moving. As long as Stella is moving in an inertial reference frame, she can claim that she is not moving and everything else is moving around her. The distance Stella measures between her origin and destination appears to decrease as her speed increases.

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Meet The Creators

  • Educator Amber L. Stuver
  • Director AIM Creative Studios, Rui Almeida
  • Narrator Bethany Cutmore-Scott
  • Producer Tom Knight
  • Sound Designer André Aires
  • Animation Mulligan Studio, Ricardo Coelho
  • Composer André Aires
  • Storyboard Artist Rui Almeida
  • Illustrator Rui Almeida
  • Character Designer Rui Almeida
  • 3D Animator Hélder Vasconcelos
  • Music AIM Creative Studios
  • Director of Production Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Associate Producer Bethany Cutmore-Scott
  • Script Editor Alex Gendler
  • Fact-Checker Brian Gutierrez

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