text: There are so many theories about this issue. String theory, parallel universes, tachyons (btw, tachyons are particles that  seem to be travelling faster than the speed of light) And to answer your question, maybe someday humans will be able to travel to another universe (if such a thing exists) But it would take tens of thousands of years of technological development. Some scientists have actually thought up ideas of how to travel to other universes, like sending nanobots containing human DNA through small wormholes, or building a particle acclerator so massive that it creates a wormhole.