The simplest shape tracked by a rotating needle (orange) is a circle, but small area shapes are possible, such as a triangle (right), created by rotating the needle while the center point tracks the circle.
Mathematicians have solved a decades-old problem related to needle rotation, which has been hailed as one of the most important mathematical results these days. If considered “impossible”, this solution must unlock answers to many other difficult questions that appear to be completely out of reach. “This paper is probably the biggest breakthrough in mathematics…
Source: www.newscientist.com