time tense relation/direction: disconnected in time/place; causally disjoint
This tense provides a way to re-contextualize the other tenses to work with relativity theory. It declares that the two events are incapable of affecting one another because there isn't sufficient time for light to travel from one event to the other before it occurs, and vice versa. To use tenses with relativity, a pu states that the reference point's event occurs in a time and place with sufficient time before the tagged event for light to travel from the reference point to the event. ba states that the reference point's event occurs after light from the tagged event could have reached it. ca states that light from the tagged event would have reached the reference point about at the same time as the reference point's event. xa'ei indicates that no light from either the reference point's event or the tagged event could have reached the other before or during the events. This is an objective form of subjective xa'e. See also: xa'e, pu, ca, ba See: https://mw.lojban.org/papri/The_proposed_fourth_tense_of_Lojban