More details can be found in Dave Bayer's very nice review in the AMS Notices which can be found in pdf form here . In a New York Times article, the author has the following interesting comments to make regarding mathematics and his reasons for including it in the play. The great thing about math is that its a kind of scientific activity that's still done in a solitary way.
Most science is now with big teams on big projects.
I don't think that math drives people crazy, but those with edgy or slightly irrational personalities are drawn to it. In short, this was a marvelously rich play about love, life and loss using the device of the mathematical theorem. David Auburn is very gifted.