A Moebius strip
If we take a long and narrow rectangle and paste together the two shortest sides after having impressed three half a torsions, we get an anomalous Moebius strip: the boundary is made of one circumpherence (as in the case of the "usual" Moebius strip), but this circumpherence is tied as in a trefoil knot.
© matematita
immagine di Gian Marco Todesco
The image belongs to the sections...:
From "fragments of topology" (From "XlaTangente")
The Moebius strip (Topology)
Further information:
http://www.toonz.com/personal/todesco
