It's not the multiverse theory; it's nothing more than the multiverse hypothesis. The idea of a multiverse is only speculation of what "could be" based on the appearance of multiple higher dimensions beyond the basic 3 + time in the mathematical equations of quantum physics and string theory...
Best answer: It's not the multiverse theory; it's nothing more than the multiverse hypothesis. The idea of a multiverse is only speculation of what "could be" based on the appearance of multiple higher dimensions beyond the basic 3 + time in the mathematical equations of quantum physics and string theory (also really just string hypothesis). The reason it's hypothesis and not theory is because there is no evidence for a multiverse, no ability for us to explore and probe into other locations within higher dimensions, and no ability for us to see or travel beyond the boundaries of what we can observe from here (the farthest observable light being the cosmic microwave background radiation). It would require observation, experimentation, and confirmed prediction of the data, as well as rigorous peer review to ensure the data was sound and there were no flaws in the studies, for the hypothesis to graduate up to the level of theory. Until then, thoughts about a multiverse are just an interesting speculation. [Note: I specified string hypothesis because the notion of vibrating strings of energy are only implied by mathematical equations. They are predicted to exist down at the scale of the Planck length, 10^-35 meters, many orders of magnitude smaller than the tiniest things we can only indirectly observe such as a top quark with a diameter of about 10^-22 meters or neutrinos at 10^-24 meters. There is currently no known way to observe anything of a smaller size, which would be required to observe and confirm strings and thus graduate the hypothesis up to the level of theory.]
And if the universe where we exist actually is infinite, and traveling an infinite amount of time in any direction will just continuously reveal more and more galaxies and therefore more and more planets, yes, an infinite universe with infinite galaxies would have infinite planets (and moons) where any number of things could happen on them. If that is the case then hypothetically, yes, there could be another planet where life formed and evolved in exactly the same direction as what happened here on Earth, including the extinction events which wiped out past species such as the asteroid impact that took out the dinosaurs, resulting in a lineage of primates that evolved into hominids and eventually humans. All the events and everything on all those infinite planets would still have to fall within the limits of the laws of physics, chemistry, etc. But the idea of a duplicate Earth being out there somewhere is also just entertaining speculation since it would take an infinite amount of time to explore an infinite amount of planets, and the universe will have a finite life with an expected ability to support life for only another 30 billion years or so, followed by an eventual heat death.
Interestingly, as I was reading about orders of magnitude and measurement of distance, I came across this: the distance of 10^10^122 meters (a 1 followed by 10^122 zeros, much bigger than a googolplex) is "According to the laws of probability, the distance one must travel until one encounters a volume of space identical to our observable universe with conditions identical to our own." [Wikipedia]
2 weeks ago