Ask HN: How exactly does EMV work in the US?
How does the implementation of EMV in the US function cryptographically? How secure is it (in your opinion)?
http://www.huffingtonpost.com/acm-the-association-for-comput...
He is a crypto professor and I am sure he can answer your technical questions about how it works.
You can find him here: http://wphomes.soic.indiana.edu/samyers/