Does Spacelike Worldlines Exist?

[kent davidge]

I'm writing some notes and I don't know if the term "worldline" is used only for timelike paths. When referring to spacelike trajectories, I have been using the word "curve" so far. Can I use "worldline" too?

 

[Ibix]

A worldline is the path followed by something through spacetime. It can therefore be timelike or null. Until we discover tachyons, it can't be spacelike.

 

[anuttarasammyak]

Trajectories you say gives me a false image that particles goes along it. So space like lines, e.g. lines of synchronization, should be called just "lines" with no world-, trajectory or orbit.

 

[Dale]

When referring to spacelike trajectories, I have been using the word "curve" so far. Can I use "worldline" too?

I would continue using curve. Worldline implies that the curve represents the position of some particle or object.