Four-Dimensional Beings
From Starbase 900 Wiki
In 2384, a shuttlecraft carrying Captain Alcar Dovan of the U.S.S. Excelsior struck an invisible space-time translation boundary in the Round Table and fell into four-dimensional space. The transition should have been instantly fatal, but, for reasons not clear at the time, Dovan instead found himself alive, in his shuttle, alongside a temporal copy of himself from two years earlier, a Lieutenant Commander Dovan. They were able to escape back to normal space.
It was later theorized that Dovan was able to survive thanks to the help of non-linear beings who inhabited four-dee space, who immediately detected him and began trying to bring him into temporal phase with their own timeless reality--resulting in Dovan's crossover with himself. However, this caused the onset of molecular decohesion, and would ultimately have been just as fatal. The four-dimensional being or beings are believed to have assisted in Dovan's escape attempt, as well.
A crack first contact team aboard the advanced science vessel Tryla Scott drew these conclusions in late March 2385 after an extensive study of the translation point. That same team was finally able to acheive initial first contact with the four-dimensional beings at around the same time. Unfortunately, communication with the beings is all but impossible due to their incomprehensible mode of existence (as our three-dimensional existence is no doubt equally inconceivable to them), so contact proceedings have advanced little beyond a primitive greeting. In the words of one version of Dovan, "It’s hard ‘nuff saing ‘hello’ to four-dimensional creatures, much less ask them for a physics lecture," and, thus, the precise scientific details of Dovan's experience have remained unclarified, although he has received a number of letters of thanks from scientists who see the potential for revolutionizing the field of higher-dimensional physics with the data gathered from the translation point he discovered.
Credits
Original information created by the players of the U.S.S. Excelsior-C simm. Permission for its use on the SB900 websites given by Alcar Dovan.