Multiverse theory

[Anomalocaris]

There is always the barrier imposed by the fact that speed of light, and age of universe, is finite.   Consequently there are continuous parts of an infinite and continuous universe that is forever beyond our reach or observation.   The boundary of what we can reach or observe is not a physical limit in the universe.  It is just a limit from behind which no information will ever come to us.  

Now let's say our whole universe is truly infinite even while the part observable to us is not, and the laws of physics is not unique to specific regions of the universe.  Then somewhere in the infinite whole universe everything which is possible anywhere would not only occur somewhere, but occur an infinite number of times, spread throughout the infinite universe.  The exact configuration of all elementary particles that makes up OUR entire observable universe is clearly possible, or it, and us, wouldn't be here.   This means IF the whole universe is infinite, there must also be an infinite number of parallel sub universes within it, each an exact replicate of the entire observable universe in which we live. Further more, there would be a vastly larger, more infinite, number of regions which resemble ours to various degree, but which are not identical to ours. Hence parallel universes in and infinite continuous universe, without even invoking anything exotic like higher dimensions.