We know that the Breach is in outerspace and that traveling through it means finding oneself in a different physical location. But in what way are you traveling? I have 4 main hypotheses on this topic:
1) Is the Breach like Star Trek's wormholes? Acting as a shortcut through the galaxy or universe? You could leave one planet and quickly end up on another. (travelling in 3 dimensions)
2) Does traveling through the Breach mean you would end up in another universe, completely unlike our own? There is no infinite branching here due to choice. There might be a limited number of such "universes" that are linked via the Breach. (still traveling in 3 dimensions)
3) Does Axiom Verge have an infinite number of parallel universes, each created as a branch of choice? This would be similar to Bioshock Infinite, where traveling through the Breach means crossing to another timeline branch and perhaps finding another version of yourself on the other side. Time does not change (as each timeline runs in parallel), but the choices made in each universe make them different from one another. (traveling in dimensions 1, 2, 3, & 5)
4) It's also possible to imagine that traveling through the Breach affects time, space, and choice. This means you could exit Universe A at any point in time and space and enter Universe B at any other point in time and space. This would be similar to DC's Crisis on Infinite Earths, where Superman of Earth A and Superman of Earth B can go back to the Stone Age on Earth C (traveling in dimesions 1, 2, 3, 4, & 5)
I think when posting to the wiki, it's best to have solid in-game evidence. But this forum can be used for more interesting and varied viewpoints such as this :)