<p>Without calculus, we wouldn't have cell phones, TV, GPS, or ultrasound. We wouldn't have unraveled DNA or discovered Neptune or figured out how to put 5,000 songs in your pocket.    </p> <p>Though many of us were scared away from this essential, engrossing subject in high school and college, Steven Strogatz's brilliantly creative, down-to-earth history shows that calculus is not about complexity; it's about simplicity. It harnesses an unreal number - infinity - to tackle real world problems, breaking them down into easier ones and then reassembling the answers into solutions that feel miraculous.    </p> <p><i>Infinite Powers</i> recounts how calculus tantalized and thrilled its inventors, starting with its first glimmers in ancient Greece and bringing us right up to the discovery of gravitational waves. Strogatz reveals how this form of math rose to the challenges of each age: how to determine the area of a circle with only sand and a stick; how to explain why Mars goes "backwards" sometimes; how to turn the tide in the fight against AIDS.    </p> <p>As Strogatz proves, calculus is truly the language of the universe. By unveiling the principles of that language, <i>Infinite Powers</i> makes us marvel at the world anew.</p>