Alan Alda has issued this year’s challenge to the world’s top scientists: What is sound? In an action-packed hour of interactive demonstrations, Alan and a team of communication experts invite the audience to explore what we hear, how we hear, and what that means for different species.

Immanuel Kant, who coined the term genius in the 1700s, defined it as the rare capacity to independently understand concepts that would normally have to be taught by another person. Since then, the spectrum of abilities that we call genius has widened, but pivotal questions remain: What exactly is genius?

Why are we drawn to symmetry? Because it provides order in a seemingly chaotic world? Because our brains are the product of the very same laws that yield the flower, the snowflake and the solar system?

Drawing on a range of disciplines, this provocative program looked at how discoveries in areas like fundamental physics, anthropology, and genomics are influencing our understanding of uniquely human characteristics.

From a bee’s hexagonal honeycomb to the elliptical paths of planets, symmetry has long been recognized as a vital quality of nature. Today’s theorists are pursuing an even more exotic symmetry that, mathematically speaking, could be nature’s final fundamental symmetry: supersymmetry.

Renowned cosmologist David Spergel joins Brian Greene to discuss the triumphs and tensions of precision cosmology, exploring remarkable successes as well as persistent discrepancies bedeviling current understanding. This program is …