Yes, Dave Bayer. I was the math consultant, but it's like joining the circus, once inside you do what you can. For one example, when I was a kid my Mom left out a Time Life book on drugs, and my brother and I were fascinated by the various photographs of spiderwebs made under the influence of different recreational drugs. That idea helped shape the "mad shack" in the film. I was also Russell Crowe's hand double, and I had a speaking part in the pen ceremony.

I personally want to thank you. As a mathematician, I always dislike the way maths is displayed in most movies. It was very refreshing to see students compute De Rham cohomology and discuss Galois theory (if I recall correctly) in a major Hollywood production.

Then again, "It's my turn" has a proof of the snake lemma in it! :-) (but the scene is much less realistic)

Russell Crowe's hand double? Does he have bad hands or something?

Not having seen the movie, I'm guessing there are scenes where Crowe needs to write some math, and it just looked more convicing by letting an actual mathematician do it for him.