As a historian and Beatle fanatic this headline immediately caught my attention: “How We’ll Forget John Lennon.” In the story by Kevin Berger, he reports on fascinating paper by Cesar Hidalgo titled “The universal decay of collective memory and attention.” Hidalgo attempts to measure the way our cultural memory—for instance, the way a hit song or artist lingers, or doesn’t—into a mathematical formula for measuring the way our collective memory fades. The results are remarkable with far-reaching implications. Here below is a brief video summarizing the paper.