Leonard Mlodinow (November 26, 1954) is an American theoretical physicist and mathematician, screenwriter and author. In physics, he is known for his work on the large N expansion, a method of approximating the spectrum of atoms based on the consideration of an infinite-dimensional version of the problem, and for his work on the quantum theory of light inside dielectrics.
He is known to a wider audience through his books, for the general public, five of which have been New York Times best-sellers, including The Drunkard's Walk: How Randomness Rules Our Lives, which was chosen as a New York Times notable book, and short-listed for the Royal Society Science Book Prize; The Grand Design, co-authored with Stephen Hawking, which argues that invoking God is not necessary to explain the origins of the universe; War of the Worldviews, co-authored with Deepak Chopra; and Subliminal: How Your Unconscious Mind Rules Your Behavior, which won the 2013 PEN/E. O. Wilson Literary Science Writing Award. He is also known through his public lectures and media appearances on programs ranging from Morning Joe to Through the Wormhole, and for debating Deepak Chopra on ABC's Nightline.