Only after having learned that the somehow only notion of equivalence of knots is definitely "ambient isotopy" I stumbled over this blog entry on ambient isotopy. (Had it been earlier!)
What bothers me since then are the two puzzles at the bottom of this page: I have no glue how to solve them.
One of the puzzles asks to show that the following two embeddings of the genus two surface are equivalent:
Can anybody give me a hint? Or - even better - is there a movie around that shows the equivalence? (Or cannot there be such a movie - for specific reasons?)
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