https://www.kuro5hin.org/comments/2015/7/27/7334/31217/8#8

I'm reminded of a science fiction short story I read years ago.  A scientist creates this race of tiny very-fast-evolving beings that live in a big terrarium or something.  They become sentient. He gives them problems, they solve them very quickly, and the scientist becomes rich and powerful with the results.  The bad guys come looking for him.  He tells his little minions "I need an impenetrable barrier around you right now!"  And fwoop up goes a barrier between the scientist and the little guys.  Then they panic because they've become disconnected from their god and I can't remember what happens next.