We don't really know much conclusive stuff about the universe yet and most things people theorise are difficult to experimentally test or verify. Still, it is fun to speculate.
I remember our lecturer, in the first cosmology class I took, likening us to ants sitting on an ant mound looking out and trying to decide what the whole world is like and how it all works.
Freude, schöner Götterfunken Tochter aus Elysium, Wir betreten feuertrunken, Himmlische, dein Heiligtum! Deine Zauber binden wieder Was die Mode streng geteilt; Alle Menschen werden Brüder, Wo dein sanfter Flügel weilt.