Sexuality and gender play a profound role in shaping identity, but for much of human history how they are determined has remained obscure. How does sexual orientation develop? What is it? Can it be changed?

Andrew Strominger, renowned for his work on black holes, string theory, and quantum gravity, joins Brian Greene to describe his latest results and how some of them may be testable …

With ever more refined techniques for measuring complex brain activity, scientists are challenging the understanding of thought, memory and emotion–what we have traditionally called “the self.”

Using brainwaves to send a Tweet, biomechanical engineer Adam Wilson demonstrates how neural prosthetic devices can allow people with motor disabilities to communicate with the outside world. Episode filmed live …

Reader’s Digest has called “Mathemagician” Arthur Benjamin “America’s Best Math Whiz.” Returning in an encore presentation, Arthur Benjamin displays feats of mental mathematical gymnastics and shares the secrets behind his skills.

For all that Darwin contributed to our understanding of the biological world, he was haunted by one vexing question: How does the incremental process of evolution suddenly produce, say, humans—animals who walk upright, communicate through language, and possess the brainpower to travel to the moon?