Peter Lassota's scientific career began on the sidewalks of Warsaw, Poland. At the urging of a grammar school teacher, the preteen Lassota entered a mathematics competition and trained for the contest with the help of his hometown's pedestrian infrastructure. "I remember we walked with our colleagues through the streets of Warsaw with a piece of chalk in our hands and a piece of paper with the problem to solve," Lassota says, "and when we had a solution, we just wrote it down on the sidewalk."












