A surface of genus 7 with one boundary curve is divided into a yellow and a white region. The white region is fixed pointwise by the mapping class obtained as product (in any order) of the 6 green Dehn twists, and it is maximal up to isotopy among subsurfaces with this property.A surface bundle over the circle
A “multiplication” of two configurations of unordered points, one on a surface, one on a disc
