BIG: There are only Two Universe-Halves.

I enjoy these postings :)

Far from being a Scientist or an Advance Math guy, I follow the Warren Buffett adage of investing in what I can comprehend.  (if Coca-Cola sells soda pop, then invest in that.)
I have never been able to fathom String Theory or multiple universes - as typically presented through educational programs and expanded by dozens of make-believe Sci-Fi shows, comic books, and movies.
So why Two Halves?
Because (IMHO) I understand Earth.  This planet has two magnetic poles which generates a field.  I can believe that all existence operates according to shared and unchanging rules - big or small, or universal.  Water boils at 100 degrees Celsius and freezes at zero.  If there is another faraway watery planet, then I would expect its water to change according to these same measures.  There could be a variance but that would only depend upon the presence of another identifiable difference within that planet.
I think that there are Two Universe-Halves, containing two [possibly polar, stacked, or otherwise dimensional] opposite 'Big Bang positions'.  Combined these two sides thus fulfill a permanently sized Co-Universe.  While one expands [our halve] the other contracts.  So that only after the one side exerts all of its energy and loses its ability to maintain its Gravity, then the second halve, now condensed to its absolute maximum, explodes.
Perhaps this is where 'dark matter Mass' goes; to fall into the other silently collecting halve.
Here on Earth, our own two Magnetic Poles flip, thereby reversing their generated field.  It only happens across vast amounts of time, but it does happen.  So I think the Universe reacts in a similar way.  However we cannot (yet) detect it, as everything we know of only exists within our halve.
Centuries ago, Mankind, and its mapmakers, decided that the world ended at an unknown cliff.  They couldn't tell that this world was round, and couldn't accept that the horizon might be looped into a repeating sphere.  Our contemporary view of the Universal 'Horizon' is that it is deemed to be endless.