Something Old, Something New, Something Borrowed, ...
F.E.J. Linton • Wesleyan Univ. Math/CS Emeritus
F.E.J. Linton • Wesleyan Univ. Math/CS Emeritus![Single Triangle; click image (or [Alt-N) for [N]ext slide](SingleTriangle.png)
Constructing the connected double cover of the circle
(with its usual topology, and depicted here as a triangle
for graphic convenience):