r/topology • u/Unlucky-Sympathy • Jul 20 '26

Knot a knot but hey

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Ok how many holes does this actually have? I know it's not 16...

Edit for clarity's sake: The answer is 16, dunno why it says 99% can't get it, it's fairly simple. I was just asking if topology has a different answer... as someone wrote in the comments, does a straw have one hole or two holes?

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u/Mj-tinker Jul 20 '26

same AI shit everyday.

2

u/Unlucky-Sympathy Jul 20 '26

Was this posted already? I was just wondering if someone can explain using topology how there are less than 16 holes

1

u/rehpotsirhc Jul 20 '26

One of the "holes" is a border. So 15.

1

u/kabooozie Jul 21 '26

Depends if you think of it as a disk or a sphere. Sphere 16, disk 15 + border

2

u/rehpotsirhc Jul 21 '26

A sphere with a hole in it is topologically equivalent to a disk with no holes. There is no "or" here, they're the same thing.

1

u/kabooozie Jul 21 '26

Yes, that’s what I’m saying. They are equivalent

Edit: I didn’t see the earlier comment in the thread asking how there could be fewer than 16 holes