When your crush sends you a picture and for a blissful moment before you open it it exists as both a nude and not a nude.
A theory based on the groundbreaking research of famed scientist and hunk Erwin Schrodinger
Erwin: I still haven't opened Dee's Snap in case it's a nude.
Albert: Has she ever sent you a nude before?
Erwin: No of course not. She's got a boyfriend. The message is a Schrodinger's clit