I think that as science continues to advance and understand the wonders of the Universe, it is only a matter of time in regards to when mankind will be able to travel between Universes. I think that the thought of such things may be fantasy to some, but I think that anything is possible.
I personally think that a brilliant idea and equations based on Einstein’s relativity theories, Ronald Mallett from the University of Connecticut has devised an experiment to observe a time traveling neutron in a circulating light beam. While his team still needs funding for the project, Mallett calculates that the possibility of time travel using this method could be verified within a decade.
Yes, I firmly believe travel between Universes will one day be possible. It might be done by locating a "doorway" in space, a form of "time travel", or perhaps we will receive help from an advanced alien race. Regardless, they say that anything that can be imagined can someday become a reality.
Yes, I think that some day there will be travel between Universes. Humans are natural born explorers, and at some point we are going to start leaving this planet, and some of us will choose not to come back. Eventually, we will spread out to every single part of the galaxy.
Given our current information we only have evidence on one Universe with many galaxies. Since we are unaware of multiple universes at this time I have to assume they don't existence and therefore it is impossible to travel between. I just look forward to the time when we might be able to travel to other galaxies.