Here's a confounding topological curiosity

boing
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Yeah. It’s probably easier to imagine it the other way. So I tried making a couple very rough pictures, and I hope you can forgive how bad they are. But here’s a rod weaving through seven holes:

Step 1

The thing is we can take the bridge on the end and slide it anywhere we want. Since it’s one that goes above the rod, we move it to match one of the others that goes above it too:

Step 2

Step 3

And now it’s become a hole that the rod goes under instead of through. Then we can do the same thing for the next bridge, matching it with one of the others that goes under the rod:

Step 4

Step 5

And so on, freeing one apparent hole after another, until there is only one left. The limitation, though, is that none of this let us change that there were bridges both above and below the rod…so we can’t actually take the last hole off the rod this way. We are stuck with that one.

Pole12

I mean, that doesn’t prove you can’t go to zero some other way, which takes more work to establish. But hopefully it does show you what you wanted.

6 Likes
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An example of the plethora of YT vids whose titles end with question marks.

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That was me. No big smokey deal. Just use wisely. Use it in peace. Don’t land on Europa.

5 Likes
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depends weather it’s a north or south pole

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In defence of YouTubers, turning off the comments is always a reasonable thing to to do. It saves you from a hurricane of hate that you can’t even imagine until you’ve posted a popular video. The only reason more people don’t do it is that it hurts you in the algorithm if you do. YouTubers have a thousand yard stare for a reason. You think you understand the depths of bile people have in their hearts? YOU DON’T KNOW. We should get combat pay, frankly, just to cover the therapy that will be needed someday.

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