interval+of+rest

  • 131Twin paradox — In physics, the twin paradox is a thought experiment in special relativity, in which a twin makes a journey into space in a high speed rocket and returns home to find he has aged less than his identical twin who stayed on Earth. This result… …

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  • 132Insect wing — Original veins and wing posture of a dragonfly. Hoverflies hovering to mate …

    Wikipedia