Scientists theorize that there is an infinitely small but non-zero chance that an atom can spontaneously wink out of existence, which, by extension, means that there is an infinitely small but non-zero chance that a molecule can spontaneously wink out of existence. Further this, and there's a chance that you could wake up tomorrow wondering what the EFF happened to your genetalia. Either that, or everything you know and love could just dissapear, litterally.
The large hadron collider is supposedly capable of creating black holes. The people running the machine think that they can control any black holes created this way.