from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Plural form of lightcone.
Sorry, no etymologies found.
If an occurence at an event A is able to causally affect another occurence at event B, there must be a continuous trajectory in spacetime from event A to event B such that the trajectory lies in or on the lightcones of every event along it.
This is because the lightcones for different frames point in different directions.
However, the two frames F and F’ may have their lightcones oriented differently.