For that last one, why not shit in your microwave and set it to 340W. That would easily allow you to test the system without buying any new appliance, except for a microwave if you don’t have one.

I’m mostly curious how higher dimensioal space could explain (perceived) expansion. Like: maybe we live in a 3d bubble embedded in an n-d space which keeps on collapsing, pouring more and more energy into our “universe”…