Fritzsch offers readers the opportunity to listen in on a meeting of Isaac Newton, Albert Einstein, and a present-day physicist. While he introduces the theory of relativity, Fritzsch teaches its sources, its workings, and the ways it has revolutionized our view of the physical world. An Equation That Changed the World dramatizes the importance of relativity, for the human race, and the survival of our planet.

"Fritzsch could not give the modern reader a more memorable introduction to the personalities and science of Isaac Newton and Albert Einstein unless somehow he could find the keys to H. G. Wells’ time machine. . . . Many readers will applaud Fritzsch for this lively but profoundly insightful book." —Booklist, starred review

"[Fritzsch] has dreamed up a dialogue between the two great physicists, helped along by a fictional modern physicist. . . . The conversation builds up to an explanation of E=mc2, and on the way illuminates the important points where Newtonian and Einsteinian theory diverge." —David Lindley, New York Times Book Review