Parallel universe or multiverse is a theory that use mostly to make scifi. Why a multiverse is possible?? There are atleast 5 reasons for that.

1. Infinite universes . We don't know what the shape of space-time is exactly. One prominent theory is that it is flat and goes on forever. This would present the possibility of many universes being out there. But with that topic in mind, it's possible that universes can start repeating themselves. That's because particles can only be put together in so many ways. More about that in a moment.

2. Bubble universes . Another theory for multiple universes comes from "eternal inflation." Based on research from Tufts University cosmologist Alexander Vilenkin , when looking at space-time as a whole, some areas of space stop inflating like the Big Bang inflated our own universe. Others, however, will keep getting larger. So if we picture our own universe as a bubble, it is sitting in a network of bubble universes of space. What's interesting about this theory is the other universes could have very different laws of physics than our own, since they are not linked.

3. Daughter universes . Or perhaps multiple universes can follow the theory of quantum mechanics (how subatomic particles behave), as part of the "daughter universe" theory. If you follow the laws of probability, it suggests that for every outcome that could come from one of your decisions, there would be a range of universes — each of which saw one outcome come to be. So in one universe, you took that job to China. In another, perhaps you were on your way and your plane landed somewhere different, and you decided to stay. And so on.

4. Mathematical universes . Another possible avenue is exploring mathematical universes, which, simply put, explain that the structure of mathematics may change depending in which universe you reside. "A mathematical structure is something that you can describe in a way that's completely independent of human baggage," said theory-proposer Max Tegmark of the Massachusetts Institute of Technology, as quoted in the 2012 article. "I really believe that there is this universe out there that can exist independently of me that would continue to exist even if there were no humans."

5. Parallel universes . And last but not least as the idea of parallel universes. Going back to the idea that space-time is flat, the number of possible particle configurations in multiple universes would be limited to 10^10^122 distinct possibilities, to be exact. So, with an infinite number of cosmic patches, the particle arrangements within them must repeat — infinitely many times over. This means there are infinitely many "parallel universes": cosmic patches exactly the same as ours (containing someone exactly like you), as well as patches that differ by just one particle's position, patches that differ by two particles' positions, and so on down to patches that are totally different from ours.

Famously, physicist's Stephen Hawking's last paper before his death also dealt with the multiverse . The paper was published in May 2018, just a few months after Hawking's demise. About the theory, he told Cambridge University in an interview published in The Washington Post , "We are not down to a single, unique universe, but our findings imply a significant reduction of the multiverse to a much smaller range of possible universes".

Hi all my dear Asgardian friends,

You all are some specific people who met in my life. I'm telling that because you are the people who have a dream about a space civilization and who gathered to make that dream true.

Do you ever had  some negative and backward thoughts about a space civilization?? I think most of you might have. You must have some questions like whether there's a developed technology for us to make a space civilization, is this will be real within our life time, how can we manage a space civilization and do we have a technology to protect and manage it. This questions may be tantalizing your head and you may get a negative idea about a space civilization thinking that it is a daydream that will never come true.

But keep all that negative and backward thoughts about the space civilization where we are going to be a partners. Though all these questions are practical and real the real love for the task we are continuing is important than all of this. So please dont be backward or faltered as we are the first witnesses of a space civilization. Dont just lure to your dream, LOVE IT!!!