The theory that if there are two pieces of bread touching the crust of the earth at any given time it makes the earth into a sandwich.
"Hey John, can you drop a slice of bread on the ground so we can test the Earth Sandwich Theory?"
A psychology essay in which you refer to the wrong topic numerous times throughout.
Man, I only got a 20% on my Physiology Essay, I wonder why....
That feeling of dread one gets when they are fearful of leaving their house because Big Time Rush will be having a live concert in their front yard.
Guy: Do you want to go out later?
Girl: No, I can't leave my house because of the Big Time Rush Uncertainty Principle.