37. Cut to Black
This one is a bit scary to think about. This theory is called a False Vaccuum. It essentially is theorizing the universe is in a stable state, but could revert to a stable vacuum at any second without warning. This would essentially mean we simply ceased existing immediately.

There’s always that risk in the day-to-day, though this may be a bit existential. Look on the bright side; this is only a theory. I, for one, plan to continue living in blissful ignorance for the time being and will hope this theory is wrong.