Forewarned, i'm super layman. Anyways, I've been wondering this all day from the thought of liquids needing less heat to boil under less atmosphere. Don't panic, i haven't JUST learned this, it just has provoked a thought. Is space expanding because of the momentum brought by the big bang, like a balloon being filled up with gas or liquid? Or is it expanding as if you poked a pin in that balloon and the hole grows bigger, from that pin point ,without control. Is it possible that matter and space is like pudding on a flat tabletop, you pore it on the table and it will eventually flatten out fully and stagnate in movement.