John and Lynn’s first  guest is Richard A. Muller, author of Now: The Physics of Time .  “Now” is a simple yet elusive concept. You are reading the word “now” right now. But what does that mean? What makes the ephemeral moment “now” so special? Its enigmatic character has bedeviled philosophers, priests, and modern-day physicists from Augustine to Einstein and beyond.

The second guest is Margot Lee Shetterly, author of Hidden Figures: The American Dream and the Untold Story of the Black Women Mathematicians Who Helped Win the Space Race. Before John Glenn orbited the earth, or Neil Armstrong walked on the moon, a group of dedicated female mathematicians known as “human computers” used pencils, slide rules and adding machines to calculate the numbers that would launch rockets, and astronauts, into space.