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by coffexx 1967 days ago
Imagine its made of putty instead of fiber. See if you can squish and stretch its surface in your mind into a sphere or flat shape without tearing it. You'll see the sock is homeomorphic with those shapes and there are 0 holes.

Likewise see if you can imagine squishing and stretching a putty coffee mug or a straw into a torus. They both have 1 hole. Like this: https://i.ytimg.com/vi/9NlqYr6-TpA/maxresdefault.jpg

1 comments

Whoa that coffee mug image is great and blew my mind