### Monday January 27, 2003

**Speaker**: Pavel Etingof (MIT)

**Title**: Feynman diagrams

**Abstract**: Feynman diagrams is a combinatorial formalism which plays a vital
role in quantum field theory. It stems from the attempt to
write explicitly the stationary phase asymptotic
expansion of rapidly oscillating integrals. While the existence of this
expansion is well known to many mathematicians, the explicit formula for
it, while being basic to every quantum physicist, is much less widely
known in the mathematical community and can rarely be found
in mathematical texts. Nevertheless it is completely elementary
and also very useful. I will explain what this formula is,
what it has to do with physics, and how it can be used in mathematics.

Prerequisites: Calculus 3, linear algebra with tensors.