At work we somehow landed on the topic of how many holes a human has, which then evolved into a heated discussion on the classic question of how many holes does a straw have.

I think it’s two, but some people are convinced that it’s one, which I just don’t understand. What are your thoughts?

  • SHITPOSTING_ACCOUNT@feddit.de
    link
    fedilink
    arrow-up
    58
    arrow-down
    1
    ·
    1 year ago

    How many holes does a donut have?

    Now make the donut higher. A lot higher. Now you have a donut-tunnel. Now make the walls thinner. Now shrink it. Now you have a straw.

    One hole.

      • bicyclingdonkey@lemmy.world
        link
        fedilink
        arrow-up
        12
        ·
        1 year ago

        That doesn’t change the topology though. Or at least you can’t without it no longer being a straw.

        A straw is the product of a circle and an interval. Either the knot doesn’t fully seal the interval, meaning it’s topology is maintained, or you completely seal the straw, changing it from 1 long interval to 2 separate intervals, changing the object entirely.

        In this situation, the straw would not be completely sealed. It is clearly inefficient, but technically there exists a path for which there is a level of force that could applied that would make the straw function.

      • RGB3x3@lemmy.world
        link
        fedilink
        arrow-up
        2
        ·
        1 year ago

        No, but that’s two holes. And it’s because the holes are not connect by a single, unbroken cylinder. It’s the material at the edge of those holes and the 90° turn at the corners that makes the holes disconnected.

        • blazerboy65@lemmy.world
          link
          fedilink
          arrow-up
          1
          ·
          1 year ago

          The edges and corners mean nothing for the purposes of counting holes. Counting holes is a concept of topology that relies on continuous deformation. All non-opening features of the object just get squished and stretched away in the process of identifying holes.

          For the purpose of counting holes a can with two openings punched into it is equivalent to a donut which we know has only one hole.

    • deeply_moving_queef@lemmy.ml
      link
      fedilink
      arrow-up
      8
      arrow-down
      6
      ·
      edit-2
      1 year ago

      This seems overly reductionist to the point where I could just as easily describe my mouth and my anus as the same hole.

      • CountZero@lemmy.world
        link
        fedilink
        arrow-up
        21
        ·
        1 year ago

        Yeah, that’s a concept that gets covered extensively in anatomy, immunology, and microbiology. It’s called “the donut model”. This is not a joke. It clearly shows how your digestive system is exposed to the outside world, similar to skin. You can obviously see why this is important immunologically, since germs can just get into the mouth/butthole in a way that they can’t penetrate skin.

        It’s one long hole.

    • veganzombeh@lemmy.world
      link
      fedilink
      arrow-up
      2
      arrow-down
      7
      ·
      1 year ago

      I understand geometrically they have the same number of holes but in my head straws still have two holes because they have an “inside” so both entrances to the inside have to be a hole.