Two kittens are on a roof. Which one falls off first?
The one with the lowest mew.
The bartender says, "We don't serve tachyons in here".
A tachyon walks into a bar.
How many theoretical physicists does it take to change a light bulb?
Two: One to hold the bulb and the other to rotate the universe.
Two neutrinos go through a bar...
Entropy isn't what it used to be.