Final answer:
The book 'The Big Short: Inside the Doomsday Machine', which inspired the movie 'The Big Short', was written by Michael Lewis.
Step-by-step explanation:
The movie The Big Short is based on a book by the same name written by Michael Lewis. It was published in 2010 and is titled The Big Short: Inside the Doomsday Machine. Michael Lewis is a well-known author in the realm of financial journalism, and this particular work focuses on the housing bubble and the financial crisis of 2007-2008. While Thomas Friedman is a renowned author, his book The World Is Flat: A Brief History of the Twenty-First Century explores globalization and is not related to The Big Short.