• DragonTypeWyvern@midwest.social
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          14 hours ago

          OP claimed there are 7 holes. Holes don’t need an exit, and I’d like to know where you think inserting something into an orbit will naturally come out in a person you want to survive the experience.

          • ftbd@feddit.org
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            14 hours ago

            Topological holes are through-holes. If there is no exit, you could continuously deform the shape until the hole is gone

              • ftbd@feddit.org
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                8 hours ago

                Correct, that’s not a hole in the topological sense. A famous example is a coffee cup: the handle is a (through-) hole, but the inside of the cup is not. As such, the coffee cup is isomorphic (=identical in terms of their overall structure) to a donut.

          • Sonotsugipaa@lemmy.dbzer0.com
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            11 hours ago

            The human body has 7 holes” is most likely a reference to [this vsauce video], and admittedly said video is the entirety of my knowledge on topology;

            that should answer “I’m really curious how you got that number”, and… probably the comment I’m replying to?

            I’m not sure I understand your rhetorical curiosity, but humans usually insert food in their mouth which is then pushed through the entire through-hole while being exposed to gastric acid and whatnot; another example are tears, entering the openings in the eyelids and coming out of the nostrils.
            Urine is instead chemically produced by the kidneys, and, unless you consider the space between molecules (which AFAIK is not within the domain of topology), that doesn’t count as one shape traversing a through-hole of another.