Is There a Universal Facial Expression of Emotion?

Ellen Ellsberg: We all think we know what emotions are, but no one can define em. She says there is no universal physical signature for any emotion that's ever been studied. And it's not easy to scientifically define what emotions are - they look different in every single situation. The way i would define an emotion is the way i conjure up a thought or belief? What is a brain memory? If you gave me a definition I wouldn't be able to tell you who i am and why  I'm here today....