Question: When you answered my really long question I remembered somthing, and thought of a new queston as well: 1) If there are infinite parralell universes, is there a parralell universe where they don’t exist? 2)Is there a parallel universe where someone has created time machines, and sealed their universes fate?

Miranda Jackson answered on 24 Jun 2015:

Those are really good and tough questions! I do not believe there is a definitive answer to either question, but I will try my best.

Is there a parallel universe where parallel universes don’t exist? If the theory of parallel universes is correct (which we do not know if it is), then one universe cannot influence what exists in any other universe, so I would say it would not be possible to have a parallel universe that excludes all other parallel universes.

If it is possible to build a time machine, then it is probable that some intelligent being in the universe will eventually build one. Even if someone does that, the universe in which that happened would still be splitting off into parallel universes. If we think of the parallel universes as taking on the shape of a tree whose branches split off indefinitely, a time machine would probably only allow travel along a branch, and would not allow someone to travel to the next branch over, without first going back to where there is a direct route to the destination branch. This is really not something which science can presently tell us. I suppose that we’d have to actually develop time travel technology to find out for sure.