Definition of world line in English:

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world line

Pronunciation: /ˈwərld ˌlīn/


A curve in space-time joining the positions of a particle throughout its existence.
Example sentences
  • But then we have a problem, because a string oscillates in space and time, and as it oscillates, it sweeps out a two-dimensional surface in spacetime that we call a world sheet (compared with the world line of a particle).
  • It does possess conserved quantities, its world line does constitute a causal process, and it is not capable of moving faster than the speed of light.
  • As in the classical twin paradox, an observer at rest relative to the preferred inertial frame measures the longest proper time between any two events on his or her world line; moving observers always measure less.
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