Today, Tom's guest is John Urschel, whose resum\u233\u includes great skill and high achievement in two areas that are not often, in fact, hardly ever, associated: football and mathematics. He is a former offensive lineman for the Baltimore Ravens who retired from the NFL at the age of 26 to pursue a career in math. The book is called Mind and Matter: A Life in Math and Football. He co-wrote it with his wife, Louisa Thomas. They’ll be speaking about the book tonight at the Ivy Bookshop in Baltimore.