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A Beautiful Mind

Russell Crowe in "A Beautiful Mind".

A Beautiful Mind is a 2001 American biographical drama film based on the life of the brilliant mathematician John Forbes Nash Jr., a Nobel Laureate in Economics. The story begins in the days of Nash as a graduate student at Princeton University and gradually focuses on its fight against paranoid schizophrenia.

In Pilot, Penny compares Leonard and Sheldon to "beautiful mind genius guys". The reference is alluded to in subsequent episodes.