world line

Noun

(physics) A path in spacetime, especially that traversed by an elementary particle from its creation to its destruction.

Japanese Meaning

物理学において、時空間内の経路のこと。特に、素粒子などが生成されてから消滅するまでに辿る軌跡を指し、「世界線」と訳される。

On the spacetime diagram, the particle's world line traced a smooth curve from its creation event to its annihilation.

時空図上で、粒子の世界線は生成事象から消滅事象まで滑らかな曲線を描いていた。

Sense（1）

(physics) A path in spacetime, especially that traversed by an elementary particle from its creation to its destruction.

world lines

（ plural ）