The multiverse theory is popular among scientists and laymen alike. Especially when it comes to science fiction films, for example 'Spider-Man: No Way Home' or 'Dr Strange in the Multiverse of Madness'.
In Marvel movies, let's take an example, there is a unique story where Peter Parker from three Spider-Man films gets together and tells each other's story that turns out to be different. So, in the real world, maybe we can meet alternate versions of ourselves in another multiverse?
For me in the universe models that I think are the most serious, the multiverse as I mentioned earlier, is a consequence of eternal inflation. In that model, we can't do cross universes.
Similarly, we most likely cannot observe the existence of other universes, in the sense of sensing them. However, if it is to observe indirectly, this possibility is still open.
Currently, physicists who are seriously researching and studying the multiverse, they are still struggling and working hard to offer ways and ideas how to indirectly observe the multiverse.
This can be done by collecting data from various studies, for example from the Cosmic Microwave Background (CMB) Radiation or using the James Webbs telescope which was just launched in December 2021.
For the details of the data taken, did not know for sure because he was not closely involved with the multiverse issue.
That's interesting, even though we can't observe the multiverse directly, but when these bubble universes expand, there is a possibility that one bubble universe collide with another. When it broke, it would release an enormous amount of energy. We can see that from the Cosmic Microwave Background data or from data taken from the latest telescopes.
