The concept of math has been around for a long time, developing independently in many different cultures. In 1650 BC, the Egyptians were creating math textbooks on papyrus, with multiplication and division tables. Geometry, like the Pythagorean theorem, was used in ancient Greece. And negative numbers were invented in China around 200 BC.Some mathematical concepts are easier to understand than others. One apple plus one apple equals two apples, for example. But when it comes to complex equations, negative numbers, and calculus, concepts become abstract. All that abstraction prompts some to wonder: Is math even real?Mathematician Dr. Eugenia Cheng has heard this question many times over her career. The quandary is the basis of her latest book, Is Math Real?: How Simple Questions Lead Us to Mathematics’ Deepest Truths. She joins Ira from Chicago, Illinois.Transcripts for each segment will be available the week after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.