What is a mock theta function?

Seminar: 
Walter Feit Memorial Lecture
Event time: 
Wednesday, December 10, 2008 - 11:30am to 12:30pm
Location: 
220DL
Speaker: 
Richard Borcherds
Speaker affiliation: 
UC Berkeley
Event description: 

Ramanujan wrote down the first examples of mock theta
functions in his last letter to Hardy. For many years
mock theta functions were rather mysterious and no
satisfactory general definition of them was known.
This problem was finally solved a few years ago by Zwegers
in his PhD thesis. His definition of mock theta
functions revolutionized the subject, simplifing many
old proofs and leading to many new results.