The concept of many worlds
One of the unresolved issues in Physics and Cosmology is the problem of the origin of laws of nature, values of fundamental constants and the alleged extraordinary coincidence between the values of these constants. Some believe that if the values of fundamental constants like the speed of light or Planck's constant were a little different, life could not appear or there could not be stars and planetary systems. Another mystery is why the Big Bang occurred and where the energy of this event came from.
One of the attempts to solve these problems is the concept (or rather: concepts) of many worlds. It is neither a scientific theory nor even a scientific hypothesis. It is rather a crazy speculation, devoid of any observational foundation or even theoretical bases - at best, designating one of the directions of a search for answers.
Two main kinds of the concept of many worlds can be distinguished. The concepts of the first kind assume that the Universe is indeed one, but in it there are (infinitely) many areas (domains), where all possible versions of the laws of nature are realised, the fundamental physical constants have all kinds of values, perhaps even the number of dimensions of spacetime is different. It is assumed that these areas (domains) are very large - larger than the volume under Hubble’s horizon, limiting what we can see and what may affect us because of the finite age of the Universe and the finite speed of the propagation of light. According to this concept, it seems to us that the in entire Universe the same laws of Physics operate, because we cannot see anything beyond the cosmic horizon, whereas beyond it there may be other areas - "other worlds" (or "other Universes") - where those rights are different, perhaps they prevent the emergence of life and the emergence of intelligent observers.
The concepts of many worlds of the second kind assume that our Universe is a "floating" part in a much larger meta-Universe, having more dimensions where structures of varied dimensions move. A collision of our structure with another would have to have been a source of energy to launch the Big Bang and the beginning of the expansion of what we call our Universe. Also in this case, the laws of nature operating in the different meta-Universes or elements of the meta-Universe would be different.
Many physicists believe that such considerations do not belong to the area of science, but to its peripherals that have always existed, and that sometimes work inspiringly, but equally often led astray.
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