In the distraction of the scandal-fever swirling through Washington and the news media, you might have missed the announcement the other day that one of the great puzzles of number theory had been solved.
What makes the news most fascinating is that the solver isn't on the faculty of a top university and wasn't known until this month to others who work in the field.
He is a Chinese immigrant in his 50s named Yitang Zhang, a onetime accountant and part-time lecturer at the University of New Hampshire who used to make sandwiches in a Subway shop.