After about 65 years of thinking about this subject, I have concluded that "the universe" had no beginning and will have no end. Its observable nature have have changed over the eons, but it is "immortal".
Contrary to "modern" physics, Space is just void. It has no physical properties other than that it exists. It is "the stage" in which energy and time interact to produce our universe.
According to M+M, the purpose of their experiment was to test the validity of Fresnel's hypothesis that "the ether is supposed to be at rest except in the interior of transparent media." M+M concluded that their experiment indicated that, "...the relative velocity of the Earth and the ether is...