See also the lovely discussion by Baez at https://classes.golem.ph.utexas.edu/category/2017/12/the_icosahedron_and_e8.html https://classes.golem.ph.utexas.edu/c

See also the lovely discussion by Baez at https://classes.golem.ph.utexas.edu/category/2017/12/the_icosahedron_and_e8.html https://classes.golem.ph.utexas.edu/category/2017/12/the_ico... .