Decades-Old Graph Problem Yields to Amateur Mathematician

It is unusual, but not unheard of, for an amateur mathematician to make significant progress on a long-standing open problem. In the 1970s, Marjorie Rice, a homemaker with no mathematical background, ran across a Scientific American column about pentagons that tile the plane. She eventually added four new pentagons to the list.

Gil Kalai, a mathematician at the Hebrew University of Jerusalem, said it is gratifying to see a nonprofessional mathematician make a major breakthrough. “It really adds to the many facets of the mathematical experience,” he said.

Source: quantamagazine.org