Have you ever fried vinegar?
I don't know why I tried it, but if you try it you'll notice at least three things.
1. the vinegar drops shrink as the water in them evaporates
2. they become darker as the percentage of vinegar increases to 100%
3. they skate across the pan due to the Leidenfrost effect
I wondered about how this would look if you could stand on one of those vinegar drops.
From this relative perspective the other drops would appear to be moving further away.
Then I wondered, how would the universe look, if viewed externally.
Could it be like frying vinegar?
What if the size of the universe was fixed, and it was the matter that was shrinking?
What would that tell us about how the laws of physics would need to change so that we, the inhabitants, wouldn't notice?
At the very least, some physical constants would need to change:
1. the speed of light
2. how mass warps space
3. (add more constants here)
The one thing that couldn't be hidden by all this is quantum physics.
In quantum physics matter and energy are converted to each other with no loss.
Atoms are formed from protons and neutrons and the equations balance out perfectly.
It's fundamentally at odds with our everyday experience - where putting something together or taking something apart involves work, effort, energy.
What if the quantum world were no different from our world, except that quantum particles get their energy from the condensing universe?