It was the mid-late 1960's when I was studying math. Quite by accident I got high in the boys crapper then went to class. I was amazed to realize how much LSD Speed, and what we called Wacky Weed quickened the mind. After that math was no problem.
Some of us even in time with assorted custom enhancements came up with equations for slip streaming hyper quantum waves as to make faster than light communications, and with some tweaking hyper-space faster than light travel possible.
Time-like, light-like and space-like intervals in special relativity can similarly be used to classify one-dimensional curves through curved spacetime. At least I think so.
Though not for organic matter.
An astronaut traveling through...well for want of a better term...Dark-Matter Space. Such a pilot, and crew would have a profoundly bad day or I should say eternity.
You see the Dark Universe is actually hell...I mean the real deal hell. Evil trapped spirits, and such. I can tell you we had some interesting adventures stuffing that crowd back into their box. However with un-personed probes it would be no problem.
These interstellar probes we long ago calculated could be sent to the nearby systems in a few moments. We of course kept this ourselves even to this day. I mean imagine what the current crop of world leaders would do with this. Mr. trump being exhibit "A".
( The above is from "The Secret History of the World", and my place in it. Volume 36 of Uncle Sydney's Private Journals.)