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nonresponsive t1_je738ou wrote

Reply to comment by stumblewiggins in You can't dig half a hole by Leafsong-Warriors

The technical definition of a hole can definitely be a contested topic.

Ask yourself, how many holes does a straw have?

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Rhovanind t1_je75sq3 wrote

Luckily we have a field of mathematics to solve problems like this. "Topology... is concerned with the properties of a geometric object that are preserved under continuous deformations, such as stretching, twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself" (Wikipedia).

From my (admittedly basic) understanding, a straw is topologically identical to a donut (torus), which has only 1 hole.

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Vincent541 t1_je7739u wrote

You topologists also say that a coffee mug is topologically identical to a donut. What's next cows are spheres?

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wj9eh t1_je77bno wrote

A cow can be simplified to a sphere.

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Dry-Faithlessness184 t1_je75t7e wrote

Not really? Hole has an absolute definition of a hollow place or opening in a surface or solid.

The better question is usually one to do with relevancy. That there are naturally 4 holes in a t-shirt doesn't matter if I'm asking about how many holes are in a damaged one. The same goes for straw, to what type of hole are you caring about.

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TheGeekno99 t1_je77brv wrote

The definition of a hole is quite simple, really (given in the other comment about topology). Or at least that's the definition of hole that works best with the real world.

(As my math teacher used to say, everything is just a bunch of conventions : We could say that lim x/x x->0 = 3, but a lot of things in the real world wouldn't be as coherent as they are with that)

Also a straw has one hole.

Another more interesting question in my opinion : If you dig a hole in a hole is it 1 hole or 2 holes ?

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Riothegod1 t1_je78ia5 wrote

My answer is “none”. It doesn’t have a hold because it is a hollow cylinder.

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