Ms. Viazovska took home the Fields Medal for her work on the sphere-packing problem in eight and 24 dimensions, the university said. The problem—how densely one can pack a space with identical spheres—used to only be solved for three dimensions or less, it said.
“In doing so, she resolved a question that had stumped mathematicians for more than four centuries: how to pack spheres—such as oranges stacked in a pyramid—as close together as possible,” EPFL said. The university added that Ms. Viazovska’s proof, which drew on other areas of math, was considered by experts to be “particularly elegant and original.”