A fake knot
We define a "fake knot" as a knot (so, a simple, closed curve in the space) that can be deformed into a circumpherence. Sometimes, it could be pretty difficult to recognize a fake knot.
The image has been realized with the program KnotPlot.
© matematita
The image belongs to the sections...:
“fake” knot (Topology)
Further information:
http://www.pims.math.ca/knotplot/