There in fact happen to be a lot of configurations where the string wraps around itself, potentially creating a tangle and eventually a knot. “But we were most happy about the response of the mathematicians.  UC San Diego Undergraduate�s Research Makes New York Times� Top Science Stories of 2007 
 
 December 10, 2007 
 
 By Sherry Seethaler 
 
 Dorian Raymer 
 
 Credit: Kim McDonald, UCSD 
 
 A southern Californian at heart, Dorian Raymer surfs, skateboards and fishes for yellowtail. In an experiment, they placed a string into a box and then tumbled it around for 10 seconds. Raymer repeated this about 3,000 times with strings of different lengths and stiffness, boxes of different size, and varying rotation rates for the tumbling. The free end of the string weaves through the coils, with a 50 percent probability of going under or over any coil. And the longer a string got, the greater the odds of knot formation became. It used the Jones polynomial—a famous math formula developed by Vaughn Jones, a mathematics professor at UC Berkeley—which automatically simplifies knots that are identical, but look different.
– You get off the subway, stash your earbuds in your pocket, and when you pull them out again, they're completely tangled—even after you painstakingly untangled them yesterday. Why does it happen every time? Well, there's actually a whole branch of science to help explain, and it's called knot theory, Wired reports. A 2007 experiment conducted at the University of California, San Diego, may shed some light on the situation. Researchers dropped string into a motorized spinning box, examining the resulting knots. They argued that knots occurred because when a string is coiled in order to fit in a small space, its end is parallel to other sections. Spinning makes it possible for that end to loop around a segment, and more spinning means more looping. In half of the 10-second spins, strings came out knotted. The longer a string was, the higher the chance of knotting—up to a point. Strings shorter than a foot-and-a-half didn't usually get knotted, and those beyond five feet long got knotty just half the time. So how to avoid knots? Stiffer cables help reduce tangling, as do smaller spaces. Or you can try a do-it-yourself method to avoid tangling.