Here’s a moment that almost everyone has experienced — you drop your phone screen down on a hard surface and hear the telltale crunch. The screen is cracked but you don’t know how bad. You pick up the phone and survey the damage. 

At that moment, looking at your cracked phone screen, have you ever wondered why it cracked in the way it did? Why do some fault lines stretch across the screen while others stop after only a few millimeters?  

Harvard scientists, in collaboration with an international and interdisciplinary team of researchers, are exploring...