Recalling his nearly two decades as Stephen Hawking’s collaborator and friend, Leonard Mlodinow brings this complex man into focus in an inspiring and deeply intimate portrayal.

When Newton discovered the law of gravity, he unified the rules governing the heavens and the Earth. Since then, physicists have been placing new forces into ever-grander theories. But perhaps the ultimate challenge is achieving a monumental synthesis of the two remaining theories—relativity and the quantum theory.

If it turns out that no one is ever free and morally responsible, what would that mean for society, morality, meaning, and the law?

Why is there an “arrow of time” in that time seems to flow in one direction, always forward? In this exclusive excerpt from his new book, Julian Barbour offers a radical answer: it doesn’t.

An exclusive excerpt from Mario Livio's new book about the life of Galileo Galilei, his discoveries and how he was challenged by science deniers.

An exclusive excerpt from Sean Carroll's new book about the essential puzzle of quantum mechanics.